I've added a new feature to the right-hand sidebar called "Top Drupal Books". This list ranks the Top 5 Drupal books based on their Amazon.com sales rank.
Currently Building Powerful and Robust Websites is in first place, but I definitely recommend checking out Learning Drupal 6 Module Development, it's really the best resource out there if you want to learn Drupal 6 coding (I have to admit, I'm a bit biased: I was one of the Technical Reviewers for the book!).
Free Book Contest!
Want to win a free copy of Learning Drupal 6 Module Development?
On June 9th, I'll select the best new module review, based on three factors: writing quality, rating fairness, and the overall usefulness of the review. The author of the winning review will receive a free copy of the aforementioned book.
If the winning reviewer happens to live in North America, I'll ship them a physical copy of the book. Otherwise, the winner will receive the e-book version, due to the high cost and general unreliability of international shipping.
Only reviews posted from today forward will be considered for this contest. That gives you roughly 2 weeks to write an awesome review.