Since we've already pointed out some non-books,
        I'll point you at:
        
        
        
        That includes three intro books: a course textbook from a
          Yale CS intro to Haskell, an online book intended for
          experienced programmers, and a book written specifically for
          the School of Haskell. Being on the SoH gives you two
          advantages: 1) exercises are presented as active code snippets
          that you can edit and run in your browser, which means 2) you
          don't have to figure out how to get a Haskell environment set
          up on your system.
        
        
        Full disclosure: I've done contract work for FP Complete,
          including participation in selecting what material wound up in
          the "Starting with Haskell" folder.