Defamation: The Bloggers' FAQ on Online Defamation Law.
Intellectual Propery: The Bloggers' FAQ on Intellectual Property
Trade Secrets: Chilling Effects Clearinghouse's FAQ on trade secret law.
Privacy: The Bloggers' FAQ on Privacy
Paper: How to Blog Safely
The guide also has an excellent set of resources.Podcasting Legal Guide
Chilling Effects Clearinghouse
Media Law Resource Center
Libel And Related Lawsuits Against Bloggers
Stanford University's Fair Use Site