The Definitive Guide to Drupal 7 is the most comprehensive book for getting sites done using the powerful and extensible Drupal content management system. Written by a panel of expert authors, the book covers every aspect of Drupal, from planning a successful project all the way up to making a living from designing Drupal sites and to contributing to the Drupal community yourself. With this book you will:

• Follow practical approaches to solving many online communication needs with Drupal with real examples.
• Learn how to keep learning about Drupal: administration, development, theming, design, and architecture.
• Go beyond the code to engage with the Drupal community as a contributing member and to do Drupal sustainably as a business.

The Definitive Guide to Drupal 7 was written by the following team of expert Drupal authors:
Benjamin Melançon, Jacine Luisi, Károly Négyesi, Greg Anderson, Bojhan Somers, Stéphane Corlosquet, Stefan Freudenberg, Michelle Lauer, Ed Carlevale, Florian Lorétan, Dani Nordin, Ryan Szrama, Susan Stewart, Jake Strawn, Brian Travis, Dan Hakimzadeh, Amye Scavarda, Albert Albala, Allie Micka, Robert Douglass, Robin Monks, Roy Scholten, Peter Wolanin, Kay VanValkenburgh, Greg Stout, Kasey Qynn Dolin, Mike Gifford, Claudina Sarahe, Sam Boyer, and Forest Mars, with contributions from George Cassie, Mike Ryan, Nathaniel Catchpole, and Dmitri Gaskin.
For more information, check out the Drupaleasy podcast #63, in which author Benjamin Melançon discusses The Definitive Guide to Drupal 7 in great detail:
http://drupaleasy.com/podcast/2011/08/drupaleasy-podcast-63-epic