Champions of the Nentir Vale
IPlay4e – Digital Character Sheets for your laptop, mobile phone, or iPad
WotC Website – Official D&D player resources from Wizards of the Coast
RPTools – Digital tools for online and hybrid RPG play
WotC’s D&D YouTube Channel – News, events, and Actual Play. Be sure to watch the Chris Perkins gaming sessions. He is the best DM I have ever seen!
WotC’s D&D Twitter Feed
Official D&D Facebook Fan Page
Power2ool – A nice way to organize gaming information. Integrates with D&D Insider.