This tutorial is an excellent example – and it’s Rails 3
Update:
This article is a better example than the one I posted earlier, works flawlessly
Second Update:
I would also recommend merging-in some of the techniques outlined in this railscast on the active_attr gem, where Ryan Bates walks you through the process of setting up a tabless model for a contact page.
Third Update:
I wrote my own test-driven blog post about it