There are a number of excellent resources available to you on the web, we've listed a few of them here:
A Day in the Backcountry - An informative slide show by the USFS National Avalanche Center.
Interactive Backcountry Tour - Test your decision making skills in this pretend backcountry outing.
Conway's Corner - Good avy info from Sarge over at Teton Gravity Research Films.
Avalanche.org - One stop shop for comprehensive avy info.
Current Avalanche Bulletins - Forecasts and bulletins compiled by the Cyberspace Avalanche Center (CSAC).
Avalanche Education - State-by-state listing of avalanche courses compiled by CSAC.
Avalanche Incidents - Learn from past avy incidents. What was done right or wrong?
Splitboard.com Avy Forum - Share your local avy observations and post questions here.
National Weather Service Homepage - Your comprehensive weather information resource.