I read the Hudak book recently and was rather disappointed. It is easy to read, but I don't think it does a good job of getting across what is remarkable about Haskell. There is some discussion of it here
which I hope might be helpful.
I don't know a good Haskell book. I learned haskell by first learning SML (from Lawrence Paulson's book) and then by reading the Haskell language standard. I would not recommend this as an efficient or effective approach.
This week I am going to read The Haskell Road to Logic, Maths, and Programming and see if I like it any better.