Here are all the CPAN distributions that start with the letter I:

i18n
I18N-AcceptLanguage
I18N-Charset
I18N-Collate
I18N-Handle
I18N-Langinfo-Wide
I18N-LangTags
I18N-String
I18NFool
I22r-Translate
I22r-Translate-Microsoft
i2c
IBGE-Municipios
IBM-LoadLeveler
IBM-SONAS
IBM-StorageSystem
IBM-ThinkPad-ACPI-Extras
IBM-V7000
IBM-V7000Unified
IBM-XCLI
ICal
ICal-Format-Natural
iCal-Parser
iCal-Parser-HTML
iCal-Parser-SAX
ICal-QuickAdd
ICanHasCheezburger-lolcats
ICC-Profile
IChing-Hexagram-Illuminatus
icli
Icon-FamFamFam-Silk
Icon-Theme-Helper
Icon-Theme-Index-Parse
Icon-Theme-List
iControl
ICQOn
ICS-Simple
ICU-Wrapper
idcheckio
IdcheckioPerl-Client
IdcheckioPerl_Client
Ident-Client
Identifier-PL-PESEL
idi
IDLtree
IDN
IDNA-Punycode
IDS
IDS-Algorithm
IDS-Algorithms
IDS-DataSource
IDS-HTTP
IDS-Test
IDS-Utils
IETF-ACE
if
if-Pragmas
ifdef
IfLoop
ignore
Igo
IhasQuery
IHeartRadio-Streams
IIIF
IIT
IkiWiki-Plugin-disqus
ikiwiki-plugin-syntax
Ikoko
IkuSan
ILL-GS
illguts
Illumos-SMF
Illumos-Zones
IM-Engine
IM-Engine-Plugin-Dispatcher
IM-Engine-Plugin-State
Ima-DBI
Ima-DBI-Contextual
Ima-DBI-Lite
Image-Animated-JPEG
Image-ANSI
Image-Base
Image-Base-GD
Image-Base-Gtk2
Image-Base-Imager
Image-Base-Imlib2
Image-Base-Magick
Image-Base-Other
Image-Base-PNGwriter
Image-Base-Prima
Image-Base-SVG
Image-Base-Tk
Image-Base-Wx
Image-Base-X11-Protocol
Image-BioChrome
Image-BMP
Image-BoxModel
Image-Button
Image-ButtonMaker
Image-Caa
Image-CairoSVG
Image-Caption
Image-CCV
Image-Checkerboard
Image-ColorDetector
Image-Compare
Image-DCMTK
Image-DeAnim
Image-DecodeQR
Image-DecodeQR-WeChat
Image-Delivery
Image-Density
Image-DominantColors
Image-Dot
Image-DS9
Image-Embroidery
Image-Empty
Image-Epeg
Image-Exif
Image-EXIF-DateTime-Parser
Image-ExifTool
Image-ExifTool-Location
Image-Filter
Image-Find-Loops
Image-Find-Paths
Image-Fixup
Image-Flight-Suborbital
Image-GD-Thumbnail
Image-GeoTIFF-Tiled
Image-GIF-Encoder-PP
Image-Grab
Image-Hash
Image-Heatmap
Image-Identicon
Image-Imager-Thumbnail
Image-ImageShack
Image-Imgur
Image-Imlib2
Image-Imlib2-Thumbnail
Image-Imlib2-Thumbnail-S3
Image-Imlib2-Thumbnail-Scaled
Image-Index-LaTeX
Image-Info
Image-Info-XS
Image-IPTCInfo
Image-IPTCInfo-RasterCaption
Image-IPTCInfo-TemplateFile
Image-JPEG-EstimateQuality
Image-JPEG-Size
Image-JpegCheck
Image-JpegMinimal
Image-JpegTran
Image-JpegTran-AutoRotate
Image-Kimdaba
Image-Leptonica
Image-LibExif
Image-Libpuzzle
Image-LibRaw
Image-LibRSVG
Image-libsiftfast
Image-Magick
Image-Magick-BarChart
Image-Magick-Brand
Image-Magick-Chart
Image-Magick-CommandParser
Image-Magick-Info
Image-Magick-Iterator
Image-Magick-NFPADiamond
Image-Magick-PixelMosaic
Image-Magick-PolyText
Image-Magick-Safer
Image-Magick-Square
Image-Magick-Stencilize
Image-Magick-Text-AutoBreak
Image-Magick-Thumbnail
Image-Magick-Thumbnail-Fixed
Image-Magick-Thumbnail-NotFound
Image-Magick-Thumbnail-PDF
Image-Magick-Thumbnail-Simple
Image-Magick-Tiler
Image-Maps-Plot-FromLatLong
Image-Maps-Plot-FromPostcode
Image-Maps-Plot-FromPostcode-LondonPM
Image-Match
Image-Mate
Image-Math-Constrain
Image-MetaData-GQview
Image-MetaData-JPEG
Image-Nikon-Index
Image-ObjectDetect
Image-OCR-Tesseract
Image-Ocrad
Image-OpenALPR
Image-OrgChart
Image-ParseGIF
Image-Pbm
Image-PBMlib
Image-PHash
Image-Placeholder
Image-PNG
Image-PNG-Cairo
Image-PNG-Data
Image-PNG-FileConvert
Image-PNG-Inflated
Image-PNG-Libpng
Image-PNG-Portable
Image-PNG-QRCode
Image-PNG-Rewriter
Image-PNG-Simple
Image-PNG-Util
Image-PNG-Write-BW
Image-Pngslimmer
Image-PNGwriter
Image-PNM
Image-Processor
Image-QRCode
Image-QRCode-Effects
Image-Quantize
Image-Randim
Image-Random
Image-Resize
Image-Resize-OpenCV
Image-Resize-Path
Image-RGBA
Image-RGBA-Text
Image-Robohash
Image-Sane
Image-Scale
Image-Seek
Image-Select
Image-Shoehorn
Image-Shoehorn-Gallery
Image-Signature
Image-Similar
Image-Simple-Gradient
Image-Size
Image-Size-FillFullSelect
Image-Square
Image-SubImageFind
Image-SVG-Path
Image-SVG-Transform
Image-Synchronize
Image-Temperature
Image-Term256Color
Image-TestJPG
Image-TextMode
Image-TextMode-Reader-ANSI-XS
Image-ThousandWords
Image-ThumbHash
Image-Thumbnail
Image-Tileset
Image-Timeline
Image-ValidJpeg
Image-VisualConfirmation
Image-WebP
Image-WMF
Image-WordCloud
Image-WorldMap
Image-XBin
Image-Xbm
Image-Xbm2bmp
Image-XFace
Image-Xpm
Image-XWD
imagecluster
Imager
Imager-Album
Imager-AverageGray
Imager-Barcode128
Imager-Bing-MapLayer
Imager-Chart-Radial
Imager-Draw-Hexagon
Imager-DTP
Imager-ExifOrientation
Imager-File-APNG
Imager-File-AVIF
Imager-File-GIF
Imager-File-HEIF
Imager-File-JPEG
Imager-File-PNG
Imager-File-QOI
Imager-File-TIFF
Imager-File-WEBP
Imager-Filter-Autocrop
Imager-Filter-Bakumatsu
Imager-Filter-Binarization
Imager-Filter-FishEye
Imager-Filter-RoundedCorner
Imager-Filter-Sepia
Imager-Filter-Statistic
Imager-Font-FT2
Imager-Font-T1
Imager-Font-W32
Imager-GIF
Imager-Graph
Imager-Heatmap
Imager-Image-Base
Imager-IMBarcode-JP
Imager-LineTrace
Imager-Montage
Imager-Plot
Imager-QRCode
Imager-Screenshot
Imager-Search
Imager-Simple
Imager-SkinDetector
Imager-Tiler
Imager-TimelineDiagram
Imager-Trim
Imager-zxing
IMAP-Admin
IMAP-BodyStructure
IMAP-Client
IMAP-Query
IMAPGet
IMDb
IMDB-Film
IMDB-JSON
IMDB-Local
IMDB-Movie
IMDB-TitleID-SearchByTitle
IMDB-TitlePage-Extract
imgautorotate
ImgIndex
imgtrim
Imgur-API
ImgurAPI
ImgurAPI-Client
Imlib2
immutable
ImplicitThis
import
Import-Base
Import-Box
Import-Export
Import-Into
Import-Into-As
Import-These
Importer
Importer-Zim
Importer-Zim-Base
Importer-Zim-EndOfScope
Importer-Zim-Lexical
Importer-Zim-Unit
IMS-CP-Manifest
in
In-Korean-Numbers-SinoKorean
inc
inc-Beer-Admin
inc-latest
incline
Include
IncomeTax-IND
IncomeTax-UK
IncPatch
Incunabulum
Indent
Indent-Form
IndexMaker
Indexuri-Apartament
indirect
INET6
Inferno-RegMgr
InfluxDB
InfluxDB-Client
InfluxDB-Client-Simple
InfluxDB-HTTP
InfluxDB-LineProtocol
InfluxDB-Writer
Infobot
InfoBrief
INFORMIXV6ALS
InfoSys-FreeDB
Ingres-Utility
Ingres-Utility-IIMonitor
Ingres-Utility-IIName
Ingres-Utility-IINamu
Ingres-Utility-Netutil
Ingres_Utility_IIName
IngyPrelude
inherit
Inheritance
INI-Examples
INI-Reader-Regexp
INI-ReadPath
Ini-Storage
INI_File
IniConf
IniConf.pm
IniFile
InitializeServer
Inky
Inline
Inline-ASM
Inline-Awk
Inline-Basic
Inline-BC
Inline-Befunge
Inline-C
Inline-C2XS
Inline-CPP
Inline-CPP2XS
Inline-CPR
Inline-FALSE
Inline-Files
Inline-FileSystem
Inline-Filters
Inline-Filters-Ragel
Inline-Flex
Inline-Go
Inline-Guile
Inline-Interp
Inline-Java
Inline-JSON
Inline-Lua
Inline-Mason
Inline-Module
Inline-Module-LeanDist
Inline-MonoCS
Inline-MzScheme
Inline-Nouse
Inline-Octave
Inline-Parrot
Inline-Pdlapp
Inline-Perl
Inline-Perl5
Inline-Perl6
Inline-Python
Inline-Rakudo
Inline-Ruby
Inline-Ruby-dRuby-Client
Inline-Scheme-Gambit
Inline-Select
Inline-SLang
Inline-SMITH
Inline-Spew
Inline-Struct
Inline-Tcl
Inline-TT
Inline-Webchat
Inline-Wrapper
Inline-WSC
Inline-YAML
InlineX-C2XS
InlineX-CPP2XS
InlineX-XS
Input-Validator
Inside
Insight-Scriptures
InSilicoSpectro
InSilicoSpectro-Databanks
Insolation
INSPEC
install
install_japerl_Framework
Installer
Integer-Partition
Integer-Tiny
Integrator-Module-Build
Intellexer-API
Interact-Later
Interchange-Search-Solr
Interchange6
Interchange6-Currency
Interchange6-Schema
Interest
interface
Interface-Param
Interface-Polymorphism
Interface-Validation
InterMine-Item
InterMine-Model
InterMine-TypeLibrary
Internals
Internals-CountObjects
Internals-DumpArenas
Internals-GraphArenas
Interpolate
Interpolation
Interpreter-Info
Intertangle-API-Glib
Intertangle-API-Gtk3
Intertangle-API-Kiwisolver
Intertangle-Jacquard
Intertangle-Punchcard
Intertangle-Taffeta
Intertangle-Yarn
Interval
IntervalTree
IntRange-Iter
Introspector
invoker
IO
IO-AIO
IO-AIO-LoadLimited
IO-AIO-Promiser
IO-AIO-Util
IO-All
IO-All-LWP
IO-All-Rule
IO-All-Securftp
IO-All-SFTP
IO-Any
IO-Async
IO-Async-JSONStream
IO-Async-Loop-AnyEvent
IO-Async-Loop-AnyEvent2-ElectricBoogaloo
IO-Async-Loop-Epoll
IO-Async-Loop-Epoll-FD
IO-Async-Loop-EV
IO-Async-Loop-Event
IO-Async-Loop-Glib
IO-Async-Loop-IO-Async
IO-Async-Loop-IO_Ppoll
IO-Async-Loop-KQueue
IO-Async-Loop-linux
IO-Async-Loop-Mojo
IO-Async-Loop-POE
IO-Async-Loop-Ppoll
IO-Async-Loop-UV
IO-Async-Process-GracefulShutdown
IO-Async-Resolver-DNS
IO-Async-Resolver-LibAsyncNS
IO-Async-Resolver-StupidCache
IO-Async-SSL
IO-Async-XMLStream-SAXReader
IO-AsyncX-EventFD
IO-AsyncX-Notifier
IO-AsyncX-Sendfile
IO-AsyncX-SharedTimer
IO-AsyncX-System
IO-Automatic
IO-Barf
IO-BindHandles
IO-Blob
IO-BLOB-Pg
IO-BlockSync
IO-Buffered
IO-BufferedSelect
IO-BufferedSelect2
IO-Busy
IO-Callback
IO-Callback-HTTP
IO-Capture
IO-Capture-Extended
IO-Capture-Simple
IO-Capture-Stdout-Extended
IO-CaptureOutput
IO-Cat
IO-Coderef
IO-Compress
IO-Compress-Base
IO-Compress-Brotli
IO-Compress-Bzip2
IO-Compress-Lzf
IO-Compress-Lzma
IO-Compress-Lzop
IO-Compress-Zlib
IO-Compress-Zstd
IO-Concurrent
IO-CSVHeaderFile
IO-Default
IO-Detect
IO-Die
IO-Digest
IO-Dir-Dirfd
IO-Dir-Recursive
IO-Dirent
IO-DiskImage-Floppy
IO-Easy
IO-EditPrompt
IO-Epoll
IO-EPP
IO-Event
IO-EventMux
IO-EventMux-Socket-MsgHdr
IO-EventQueue
IO-Events
IO-ExplicitHandle
IO-Extended
IO-FD
IO-FDPass
IO-FDpassData
IO-FDSaver
IO-File-AtomicChange
IO-File-Cached
IO-File-CompressOnClose
IO-File-Cycle
IO-File-flock
IO-File-Lockable
IO-File-Log
IO-File-Multi
IO-File-MultiLines
IO-File-String
IO-File-WithFilename
IO-File-WithPath
IO-Filter
IO-Framed
IO-Ftp
IO-Glob
IO-Handle-Moose
IO-Handle-Packable
IO-Handle-Record
IO-Handle-Rewind
IO-Handle-unread
IO-Handle-Util
IO-HTML
IO-HyCon
IO-Infiles
IO-InSitu
IO-Interactive
IO-Interactive-Tiny
IO-Interface
IO-IPFinder
IO-Iron
IO-Iron-Applications
IO-Journal
IO-K8s
IO-KQueue
IO-Lambda
IO-Lambda-Inotify
IO-Language
IO-LCDproc
IO-Lcdproc-Client
IO-Lcdproc-Screen
IO-Lcdproc-Widget
IO-LockedFile
IO-Mark
IO-MiddleMan
IO-Moose
IO-Multi
IO-MultiPipe
IO-Multiplex
IO-Multiplex-Intermediary
IO-Multiplex-KQueue
IO-Mux
IO-Mux-HTTP
IO-NestedCapture
IO-NonBlocking
IO-Notification-Recursive
IO-Null
io-page
IO-Pager
IO-Path-Mode
IO-Path-More
IO-Path-XDG
IO-Pipe-Producer
IO-Pipeline
IO-Pipely
IO-Plumbing
IO-Ppoll
IO-Prompt
IO-Prompt-Hooked
IO-Prompt-I18N
IO-Prompt-Simple
IO-Prompt-Timeout
IO-Prompt-Tiny
IO-Prompter
IO-Pty-Easy
IO-Pty-HalfDuplex
IO-React
IO-ReadHandle-Chain
IO-ReadHandle-Include
IO-ReadPreProcess
IO-ReStoreFH
IO-Reverse
IO-Select-Trap
IO-SendFile
IO-SessionData
IO-Shaper
IO-SigGuard
IO-Simple
IO-Slice
IO-Sockatmark
IO-Socket-Async-SSL
IO-Socket-ByteCounter
IO-Socket-CLI
IO-Socket-DNS
IO-Socket-Forwarder
IO-Socket-INET-Daemon
IO-Socket-INET-Host
IO-Socket-INET6
IO-Socket-IP
IO-Socket-Multicast
IO-Socket-Multicast6
IO-Socket-PortState
IO-Socket-PortState-cPanel
IO-Socket-RedisPubSub
IO-Socket-SecureSocks
IO-Socket-SIPC
IO-Socket-Socks
IO-Socket-Socks-Wrapper
IO-Socket-SSL
IO-Socket-Telnet
IO-Socket-Telnet-HalfDuplex
IO-Socket-Timeout
IO-Socket-TIPC
IO-Socket-UNIX-Util
IO-Statistic
IO-Statistics
IO-Storm
IO-Stream
IO-Stream-Crypt-RC4
IO-Stream-HTTP-Persistent
IO-Stream-MatrixSSL
IO-Stream-Proxy-HTTPS
IO-Stream-Proxy-SOCKSv4
IO-Stream-Proxy-SOCKSv5
IO-String
IO-stringy
IO-StructuredOutput
IO-Stty
IO-SWF-Editor
IO-Tail
IO-Tee
IO-Term-Status
IO-Termios
IO-TieCombine
IO-Tokenized
IO-Tty
IO-Tty-Util
IO-Uncompress-Untar
IO-Unread
IO-URing
IO-Util
IO-Vec
IO-Vectored
IO-WithHeader
IO-WrapOutput
IO-YAML
IO-Zlib
IO_CSVHeaderFile
IOas-CP932
IOas-CP932IBM
IOas-CP932NEC
IOas-CP932X
IOas-SJIS2004
IOC
IOC-Lite
IOC-Slinky-Container
Ioctl
IOD
IOD-Counter-Simple
IOD-Examples
iodbc-wwwtools
iodbc_ext
IODEF-DBI
Iodef-Pb
Iodef-Pb-Format
Iodef-Pb-Simple
IOLayer-Base64
IOLayer-MD5
IOLayer-QuotedPrint
IOLayer-StripHTML
IOMux
IOMux-HTTP
Ion
ios_get_interfaces
IOSea-Browse
IP-Addr
IP-Address
IP-Anonymous
IP-China
IP-ChinaISP
IP-Country
IP-Country-Data
IP-Country-DB_File
IP-Country-DNSBL
IP-Country-NetOp
IP-CountryFlag
IP-Decimal
IP-Geolocation-MMDB
IP-Info
IP-IPwhere
IP-Location
IP-QQWry
IP-Random
IP-RangeCompare
IP-Registry
IP-Route-Reject
IP-Tools
IP-Unique
IP-World
ip2location-perl
IPA
IPC-AnyEvent-Gearman
IPC-Cache
IPC-Capture
IPC-ChildSafe
IPC-Cmd
IPC-Cmd-Cached
IPC-Command-Multiplex
IPC-Concurrency
IPC-Concurrency-DBI
IPC-ConcurrencyLimit
IPC-ConcurrencyLimit-Lock-MySQL
IPC-ConcurrencyLimit-Lock-NFS
IPC-ConcurrencyLimit-Lock-Redis
IPC-DirQueue
IPC-Door
IPC-Exe
IPC-Filter
IPC-Fork-Simple
IPC-ForkPipe
IPC-GimpFu
IPC-LDT
IPC-LeaderBoard
IPC-Lite
IPC-Lock
IPC-Lock-RabbitMQ
IPC-Lock-WithTTL
IPC-Locker
IPC-Lockfile
IPC-Message-Minivan
IPC-Messaging
IPC-MM
IPC-MMA
IPC-Mmap
IPC-Mmap-Share
IPC-Mmap-SimpleShare
IPC-MorseSignals
IPC-MPS
IPC-Notify
IPC-Open2-Simple
IPC-Open3-Callback
IPC-Open3-Simple
IPC-Open3-Utils
IPC-OpenAny
IPC-PerlSSH
IPC-PerlSSH-Async
IPC-Pidfile
IPC-Pipeline
IPC-Pleather
IPC-PrettyPipe
IPC-PubSub
IPC-Queue-Duplex
IPC-QWorker
IPC-ReadpipeX
IPC-Run
IPC-Run-Fused
IPC-Run-Patch-Setuid
IPC-Run-SafeHandles
IPC-Run-Simple
IPC-Run3
IPC-Run3-Shell
IPC-Run3-Simple
IPC-RunExternal
IPC-RunSession-Simple
IPC-SafeFork
IPC-ScoreBoard
IPC-Semaphore-Concurrency
IPC-Semaphore-Set
IPC-Semaphore-SmokeSignals
IPC-Serial
IPC-Session
IPC-Shareable
IPC-SharedCache
IPC-ShareLite
IPC-ShellCmd
IPC-Shm
IPC-Shm-Simple
IPC-Signal
IPC-Signal-Force
IPC-Signal-Translate
IPC-Simple
IPC-SRLock
IPC-System-Locale
IPC-System-Options
IPC-System-Simple
IPC-SysV
IPC-Transit
IPC-Transit-Router
IPC-XPA
ipc_shareable
IPC_SysV
IPCamera-Reolink
IPChains
IPDevice
IPDevice-Allnet-ALL4000
IPDR
IPDR-Collection
iPerl
Ipernity-API
IPGen-V4
ipgrep
Iphone-SMS
iphoto
IPIP
Ipmitool
iPod-Squish
iPodDB
IPsonar
IPTables
IPTables-ChainMgr
IPTables-IPv4
IPTables-IPv4-DBTarpit
IPTables-libiptc
IPTables-Log
IPTables-Mangle
IPTables-Parse
IPTables-Rule
iptckeyword
IPv6-Address
IRC-Art
IRC-Bot
IRC-Bot-Hangman
IRC-Bot-Log-Extended
IRC-Channel-Log
IRC-Client
IRC-Client-Plugin-DiceRolls
IRC-Client-Plugin-Factoid
IRC-Client-Plugin-Github
IRC-Client-Plugin-HNY
IRC-Client-Plugin-Logger
IRC-Client-Plugin-NickServ
IRC-Client-Plugin-Reminders
IRC-Crypt
IRC-Formatting-HTML
IRC-FromANSI-Tiny
IRC-Indexer
IRC-Log
IRC-Log-Colabti
IRC-Log-Textual
IRC-RemoteControl
IRC-Server-Tree
IRC-Toolkit
IRC-Utils
IRCDHelp
iRedAdmin
IRI
IronMan-Schema
IRR
Irssi-Bot-BasicBot-Pluggable
Irssi-Script-InfoParser
Is-Bot
IS-Conf
IS-Init
Is-Kennitala
ISA
ISAL-Crypto
Isam
ISBN-SearchByTitle
ISO-15924
ISO-639
ISO-639-3
ISO-639-5
ISO-639_1
Iss-Ah-Predictor
IsUTF8
Iter
Iterate
Iterator
Iterator-Array-Jagged
Iterator-BreakOn
Iterator-Breathe
Iterator-DBI
Iterator-Diamond
Iterator-File
Iterator-File-Line
Iterator-Flex
Iterator-GroupedRange
Iterator-IO
Iterator-Merger
Iterator-Misc
Iterator-Paged
Iterator-Records
Iterator-Records-Lines
Iterator-RoundRobin
Iterator-Simple
Iterator-Simple-Lookahead
Iterator-Simple-Util
Iterator-ToArray
Iterator-Util
iThenticate-API-Client
iThenticate-API-Request
Ithumb-XS
ITM
iTransact-Lite
Itsabear-Junks-Hello
iTunes-Sid
IUP
IURL-XS
Ivrs
IWL
IWL-SWFUpload
Ixchel
IxNetwork