The American Homebrewers Association page on the Brewers Association website:
American Homebrewers Association
How To Brew by John Palmer is one of the most useful books to a homebrewer, new and old. Palmer graciously put the first edition of his book on the internet. It is free to read and print.
www.howtobrew.com
Homebrew Talk forums are a good source of information. Run a quick search can often yield needed information, especially in a hurry.
Homebrewtalk.com
Brew365 is a great source of information and recipes. They even list out recipes to clone some of the popular commercial brews.
www.brew365.com
Brew-Monkey is another repository for information and recipes. Especially of note are their interviews with craft brewers.
www.brew-monkey.com
Hopville is a budding community for homebrewers and their recipes. It's still under development, but instead of being "in beta" it's been "getting bettah" all the time.
http://hopville.com/whats-brewing
Basic Brewing is run by James Spencer and is a weekly podcast on homebrewing and general beer topics. His video offerings are a little more intermittent but just as good. The nice thing about audio is that you can learn something useful even while you are doing some sort of menial activity. If you have never watched or listened to any of his productions, scan the archives for anything of interest.
Audio Video