Anything you can find on YouTube with the Ripken brothers training middle infield. Mike Candrea also has a nice video out that includes general infield reps.
Not sure about books, but you should be able to fill a couple of hours of your time watching videos on YouTube...and if you really want to go off the deep end, you can read FFS's thread on the Auburn Hop, and decide for yourself if it is a worthwhile endeavor.