Course material created by instructors
Short, dense, classic ways to hit the ground running
Curated resources put together by Haskellers:
Manuals and guides that cover common Haskell tooling:
The Cabal guide is a good start but there's a lot to learn:
Documentation for Haskell libraries is typically available on Hackage. We also have specialized tools for searching across it, not only by name, but by type.
The Haskell 2010 language report is available online here.
A PDF version is available here.
It can also be downloaded as a darcs repository:
$ darcs get http://darcs.haskell.org/haskell2010-report