If you are planning on growing commercially, the only really good current up to date book is

Hydroponic Crop Production Lon Dalton and Rob Smith
There is a description at http://www.alabamahydroponics.com/GH/store/books/books.htm

If you are doing hydroponics as a hobby, there are many sources of information to get you started.

I'll second the advice to get Smith's book. I also can recommend a good consultant who is worth his weight in gold and will save you every penny.

Here is a link that might be useful: Gordon Creaser Hydroponic Consultant