There's a couple of reasons why I generally don't like repair books:

The first is that as soon as a manufacturer comes out with a new product, your repair book is obsolete. Of course, bicycle and component manufacturers rarely come out with new products, right?.....NOT! Unless you get annual updates for your book, you're SOL for any component, design, part, tool etc. which is introduced to the market after you buy your book.

Second, there are so many different types of products out there right now, dating back years and years (e.g. people still ride bikes built in the 1970's), in addition to numerous generations of the same product, that unless you buy a book like Barnett's (which is expensive and thicker than a telephone book) most repair books can't possibly cover how to service all the different types of products out there.

The best repair guide I've used is constantly updated, includes photos and step-by-step explanations for virtually every component likely to still be in use and is FREE:

http://www.parktool.com/repair/

Sometimes when making a repair I'll set up my laptop right on my workbench and go from there, or I'll print out the instructions and work off those.

Another great resource is Sheldon Brown's site:

http://www.sheldonbrown.com/harris/hub.html

I have a couple of dusty old repair books which I haven't used in years, because the 2 sites above provide me with 99% of all the info I ever need. Any other info I might need I get off these message boards or from the manufacturers' web-sites for the particular component I'm having an issue with.

Bob