I have 2 favorite books for bicycle repair. They are: Richards' Bicycle Repair Manual and Sidwells, Chris Bicycle Repair Manual. These books offer insight into popular as well as not too well known types of bicycles and their drivetrains (such as internal hub gears). I used them for all my bicycle maintaince needs.
I purchased these books in a bookstore. The LBS near my house usually only stock bike magizines or DVDs featuring bike stunts.