Even before I bought my bike last summer, BF bought me a copy of Anybody's Bike Book (by Tom Cuthbertson, I think). It's very clearly written, even for the mechanically challenged like me. Check the Bike Maintenance forum on here and post a question. Someone will post a link.

Also, sometimes bike shops will fix minor things for free or pretty cheaply. I just make sure to give them my business for other things. This last time it was a pedal wrench and a few packages of Clif shot blocks.

Edit: Your bike shop may also hold maintenance classes. The one where I bought my bike does.