I'll be living and working in Yosemite for the next 9ish months and I want a few books before I get out to the Valley. I plan on doing lots of bouldering and moderate cracks before and after work. I'm slowly learning how to aid climb (I am from Arkansas) and want to get some larger multi-pitches done while I'm out here.
Get yourself the Sonora Pass guidebook by Brad Young. For moderate cracks make sure to check out the following crags: Two Mile Bar, The Grotto, Hamburger Rock, The Lucky Draw, Burst Rock, and Pygmy Pillars. The Sonora pass will get you up to speed on crack climbing in no time.
Note that Sonora pass climbers like to keep things on the down low so most of this isn't on MP, it's all in the book, though.