- Learning Haskell
- Learn You a Haskell for Great Good
- Real World Haskell
- FPComplete's School of Haskell
- Haskell Wikibook
- Write Yourself a Scheme in 48 Hours
- Parallel and Concurrent Programming in Haskell
- Natural Language Processing for the Working Programmer (An Introduction to NLP and Haskell)
- Intro to Computing with Haskell
- Haskell the Hard Way - Learn Haskell Fast and Hard
- Haskell School of Music
- Introduction to Haskell (UPenn/byorgey)
- Introduction to Haskell (University of Virginia/Shuklan)
- Art of Recursion (UPenn/byorgey)
- Functional Systems in Haskell (Stanford)
- Haskell Course - Tony Morris/NICTA
- C9 Lectures: Dr. Erik Meijer - Functional Programming Fundamentals
- HaskellWiki - Programming Contests
- Haskell 99 Problems
- Exercism
- HackerRank
- Talentbuddy
- Daily Haskell Exercises
- Haskell Koans
- Learn You A Haskell Exercises
- Rosalind - Bioinformatic Exercises
- 1 Haskell A Day
- Haskell Reddit
- Haskell Weekly News
- The Haskell Cast
- Haskell Planet
- StackOverflow - tagged Haskell
- QuestHub - Haskell Realm
- The Haskell Cast
- NY-Haskell Meetup
- London Haskell Meetup
- Haskell Video Collection (compiled by cdsmith)
- Haskell from Scratch
- Code Deconstructed
- InfoQueue - Haskell
- Purely Functional Data Structures by Okasaki
- Purely Functional Data Structures published since Okasaki
- More at HaskellWiki
- Why Functional Programming Matters by John Hughes
- The History of Haskell
- Monads for Functional Programming by Philip Wadler
- More at the HaskellWiki.
- The Glasgow Haskell Compiler
- lpaste - Pastie Service
- Haskell Style Guide (tibbe)
Write yourself a Scheme in 48 hours. A tutorial that takes a practical approach to teach Haskell, assumes basic knowledge of Haskell though(read the first few chapters in LYAH in advance and it'll be fine). http://en.m.wikibooks.org/wiki/Write_Yourself_a_Scheme_in_48_Hours
It's a highly recommended read for people who use Haskell as first language. It told me essentially how you attack problems with programming.