Honey Bee Hobbyist: The Care and Keeping of Bees. Don't let the title fool you: Dr. Gary has over 30 years experience as a beekeeper so there's something in the book for everyone, even established beekeepers and it's well written, organized, and easy to understand. If you're looking to get into beekeeping then this is the very first reference you should get -and it may well be the only one you need!
The book is filled with some excellent macro and closeup images as well (I was one of the photographers who contributed photos).
You can order it from Amazon -and for the record I make no money from that link.