Chad-

I recently purchased "The Haskell School of Expression" by Paul Hudak.

http://books.google.com/books?id=lQbth9j5j9oC&dq=the+haskell+school+of+expression&pg=PP1&ots=JPct_cBYJH&sig=Hr3Wz2vqZ5a-TjBoJkxE9QgWPuk&hl=en&sa=X&oi=book_result&resnum=1&ct=result

I felt that it was a pretty decent introduction to the language. However, I was disappointed by its use of an (apparently) Win32 only library. While I haven't found the time to work through the exercises, that's what the book said. This may have changed. I plan on working through the book again in a few weeks after my summer classes are over.