Last year in February, I introduced Robert Douglass to Matt Wade, an editor at Apress. Yesterday, 11 months later, I received a copy of the book, Building online communities with Drupal, phpBB and Wordpress, as a result of that introduction.
In roughly 200 pages (the part about Drupal), Robert Douglas teaches you everything you need to know in order to install, configure and maintain a Drupal site. I only spent 2 hours exploring the book so far and already it teached me some new things about some of the contributed modules. I doubt any Drupal user will be disappointed with this book. Highly recommended.