Learn About Invasive Plants
Weeds Gone Wild: Alien Plant Invaders of Natural Areas is a Web-based project of the Plant Conservation Alliance's Alien Plant Working Group. It includes lists of invasive plants throughout the U.S., background information on the problem of invasive species, fact sheets, and suggested alternative plants.
The Invasive and Exotic Weeds page of Invasive.org lists hundreds of species with links to information and photos.
Organic Gardening for Dummies, 2nd edition
In the first edition of Organic Gardening for Dummies, by Ann Whitman, you'll find an incredible amount of information on growing organically. I was fortunate enough to have the opportunity to revise and update the 2nd edition, which has just been published. I included some new information on making the case for organic growing as well as new products and techniques. It's a great reference, if I do say so myself, for new and experienced gardeners alike.