The Definitive Guide to Grails

This book, by Graeme Rocher and Jeff Brown, gets a big FAIL for already being out of date. My goal in picking up a tech book is to get the cookie-cutter stuff in the tutorial to work right away, and then work my way deeper, explore the capabilities, and extend as I need, later. Examples started breaking in chapter 2, in the tutorial.
On the one hand, Grails is evolving quickly, so it is understandable that the book gets out of date. On the other hand, dropping $45 for a book where the basic tutorial doesn't work in six months means it's a bit premature to be writing books on the subject, that sort of content should probably be in a wiki that gets updated as the project evolves.