Programming
Pro JavaScript Design Patterns (Recipes: a Problem-Solution Ap)Pro JavaScript TechniquesPro Drupal Development
Pro JavaScript Design Patterns (Recipes: a ...
by Ross Harmes
$36.51
Finally, somebody has approached Javascript with a view toward patterns.
Pro JavaScript Techniques
by John Resig
$38.46
A nice overview of techniques. Sometimes requires another source to get a fuller understanding.
Pro Drupal Development
by John K. VanDyk
$20.91
The best I could find for working inside of the drupal php hierarchical system.
Prototype and Scriptaculous in Action [Ajax]Learning Perl, Fourth EditionLearning jQuery: Better Interaction Design and Web Development with Simple JavaScript Techniques
Prototype and Scriptaculous in Action [Ajax]
by Dave Crane
$29.69
Excellent tutorial book with good example code.
Learning Perl, Fourth Edition
by Randal L. Schwartz

I cut my teeth on this book. It is still probably my favorite all time programming book.
Learning jQuery: Better Interaction Design ...
by Jonathan Chaffer
$31.57
jQuery is cool, no doubt. Sometimes it can be a little mysterious. This book reveals the hidden points.
Perl Cookbook, Second EditionMinimal Perl: For UNIX and Linux PeopleAjax in Action
Perl Cookbook, Second Edition
by Tom Christiansen
$32.97
Someone has done it before. At least something close to what you need to do.
Minimal Perl: For UNIX and Linux People
by Tim Maher
$29.67
A good intro to Perl and also helps you write concise code and even 1 liners for the command line.
Ajax in Action
by Dave Crane
$29.67
I think this is the best treatment of Ajax. It also gives a lot of information about javascript programming in general.