The Fundamentals of SEO for the Average Joe-- Alyssa Ast's book
WordTracker-- free keyword tool
Google Adwords-- keyword tool
SEO Tools-- keyword density analyzer
The Practical Freelance Writer's Guide to Author Websites by Angela Atkinson-- A valuable resource for creating author websites, as well as optimizing author websites.
Search Engine Optimization- SEO and SEM tips.
Do you know of a useful seo/sem site, blog or other resource? Contact Alyssa to add it to the list!