The cocos2d Programming Guide provides in-depth documentation for writing applications that use cocos2d. Many topics described here reference the cocos2d API reference, provided separately.
If this is your first time reading about cocos2d, we suggest you start at Beginners' Guide.
This documentation is valid for v0.99.x If you find any errors, please, either edit the wiki or send an email to the forum. Thanks.
Also, don't forget to read the cocos2d for iPhone best practices
Included with Cocos2d are some samples and tests - useful for ideas on how to do things.
Many useful code snippets have been posted on the forum. It can be difficult to find them, this page tries to gather them all.
Finally you can download/buy some open-source / commercial cocos2d for iPhone games