Using the special link below you can get a 33% discount on Open Design's Kobold Guide to Game Design, Vol 1. in PDF format. The offer expires February 23rd - so grab it while it lasts!
~ CLICK HERE TO GET THE DISCOUNT ~
It's an excellent book. You can see what I thought about in a previous post, "3 Books To Improve Your RPG Game Before The New Year".
A print version of the book is also available from Amazon.com.