Well, it's not a book so much as it's a series of comic books. The most cost-effective way to get it will be to get the compendium editions. There are two so far, collecting eight volumes each (or, roughly 45 single issues per comendium):
It's pretty good stuff. A bit talky, but good. The series is not complete, by the way; the two compendiums run through issue #96, and issue #108 hit comic stores a week ago. That means you'll have a looooong wait for the third compendium!
I've added this to my "to read" list.