The Barefoot Gardeners Yahoo group mailing list contains good discussion

Code Green Community for sustainability in the Tampa Bay area

In Grave Danger of Falling Food - video intro by Bill Mollison

Permaculture: A Beginner's Guide

Permaculture: Sustainable Farming, Ranching, Living... by Designing Ecosystems that Imitate Nature

Yet another Intro to Permaculture
- by the National Sustainable Agriculture Information Service

Permaculture Design Course pamphlets
- from a 1983 course taught by Mollison

Gaia's Garden
- decent introductory book on applying permaculture to gardening

Introduction to Permaculture
- very good book by Mollison with many practical examples

Permaculture: A Designers' Manual
- "the permaculture handbook" by Mollison

Permaculture: An Approach to Sustainable Living - good brief overview