Iphone Application Source
http://www.theiphonedev.com/SourceCode/tabid/143/Default.aspx
http://kwigbo.com/
http://www.iphonecodesource.com/
http://mobileorchard.com/31-iphone-applications-with-source-code/
http://visionwidget.com/tuts/webtuts/509-open-source-iphone-apps-in-app-store.html
http://blog.mencio.com/?p=431