WebWork is a very popular framework and community. As such, there are many articles, presentations, and books about WebWork. Here is just a sample.

Books

Presentations

WebWork + AJAX: A winning combination - Patrick Lightbody, JavaZone 2005
WebWork in Action: An introduction to WebWork
Jason Carreira's slides and example code (4/04): webwork-talk.zip
[Writeup of Mike's Talk at TSS on WebWork] (7/03)
Mike's PPT Presentation from TSS Symposium: http://blogs.atlassian.com/rebelutionary/archives/000200.html
- Some Japanese translated information (including the presentation above): http://www.mobster.jp/webwork/
Another PPT presentation from Rick Salsa, Groove Systems: http://www.groovesystems.com/training/java4/webwork.ppt

Getting started with WebWork 2.1.7
Building with WebWork on TheServerSide (11/03): http://www.theserverside.com/resources/article.jsp?l=WebWork2
A brazilian portuguese tutorial teaching the main concepts and features of Webwork (14/04):
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The official WebWork Blog can be found here.