According to the table of contents, chapter 12 will be on "Working with Grails" and chapter 13 is on "Grails and Web Services". This is according to [URL=http://media.pragprog.com/titles/sdgrvr/toc.pdf=the table of contents[/URL] of the beta book. Amazon doesn't have the final table of contents, but I guess that there will be no difference, or no extra chapters, since amazon states that the book is 250 pages, just like the ToC says.
As Alaa Nassef says, there are two chapters at the end, but Groovy Recipes is hardly a Grails book.
The format of the book is to ask a common question -- "How do I parse an XML document with namespaces?" -- and show you the few lines of code it takes to accomplish your goal. Ideally, all you'll need is the code to solve the problem, but each recipes has a couple of paragraphs (or in rare cases, a couple of pages) to explain all of the moving parts.
Trying to learn a web framework 6 lines of code at a time isn't the optimal way to tackle something like that. There are plenty of good resources out there for Grails -- Def Guide to Grails and Getting Started With Grails are two very good ones. (The latter book is a free PDF.) While both are a bit long in the tooth right now (1.0 was just released this month, and both books are based on 0.3), both are in the process of being updated to 1.0.
In the meantime, I have a series of articles at IBM DeveloperWorks called Mastering Grails. It's a good source for current information about Grails. You can also subscribe to the Atom feed at a website I run -- About Groovy.