Peachpit Press has posted a free chapter from the new DVD Studio Pro book. They have a free chapter and hands on media files on how to create custom DVD menus (just click the Sample Content tab).
You can view it here as well a check out the whole book.
"Updated for DVD Studio Pro 4.2.2, this best-selling, Apple certified guide uses striking real-world footage to build four complete DVDs and share a Blu-ray disc. It covers how to use DVD Studio Pro on its own, as well as how to integrate it into your workflow with Final Cut Pro 7, Motion 4, and Compressor 3.5. Each lesson takes you step-by-step through an aspect of DVD creation and finishing, with hands-on projects for you to complete as you go."