Real World Haskell. Hierarchical Libraries. Example code. To get a feel for what real world Haskell looks like, here are some examples from various popular Haskell projects.
To start learning the language, good places to start are Learning Haskell, Haskell in 5 steps, and Books and tutorials. More code may be found on the wiki. 99 questions/90 to 94. This is part of Ninety-Nine Haskell Problems, based on Ninety-Nine Prolog Problems.
If you want to work on one of these, put your name in the block so we know someone's working on it. Then, change n in your block to the appropriate problem number, and fill in the <Problem description>,<example in Haskell>,<solution in haskell> and <description of implementation> fields. 1 Miscellaneous problems.