For the newbies, or those who prefer to see it done, rather than read about it, I've had good luck with some of the DVD's available from
www.probikekit.com.
I have their DVD's for brakes, gears, headsets, and handlebar taping. At less than $7 US each, they're a bargain...the material is presented well, and the camera angles really helped me to figure out what's what on the bike (much more so than some of the cryptic drawings in the various books I have).