More than two weeks ago "Practical RichFaces" 2nd edition by me and Max Katz was finally published. That book intended to guide you throug JSF 2 and RichFaces 4 development. It includes huge set of real-world examples for all the components including for example support of complex data structures in RichFaces tables and trees components. Besides it should help you to go through major base changes in RichFaces 4 such as redesigned Skins, Ajax options and Requests queueing.
Finally it contains separate chapter dedicated to completelly redesigned RichFaces CDK. It will guide you through the process of creation the component from scratch highlighting all the features from component development kit which are intended to make the life of component developer much easier.
So if you went through the book - let us know how it was!
Checout book examples from github.