See the references provided at http://forrest.apache.org/docs/project-sitemap.html
Also follow the "Supersonic Tour" ... http://cocoon.zones.apache.org/ This is a live Cocoon application to demonstrate and explain some techiques. If you don't have the Cocoon source local, then you can see it via the SVN webserver http://svn.apache.org/repos/asf/cocoon/blocks/tour/trunk/ -David