I have been helping several people on twitter over the last few weeks to get started with Cocos2d – http://www.cocos2d-iphone.org/ – so I thought I would put together a list of useful sites and other information all in one spot.
Your first stop should be the Cocos2d documentation and forums:
People to follow on Twitter:
Useful tools to help with game Design:
Feel free to add more links in the comments section below.