I have just uploaded a new ActionScript 3 reference / online documentation API to Google App Engine. Basically, the service takes an ActionScript 3 class name (or a fragment of a class name) and returns the URL for the online documentation for the specified class.
All responses are returned as JSON encoded data.
Right now, it returns API information for Flash Player 9, Flex 3 and AIR 1.1. It is possible to add new API information.
You can read more information on the service page at:
Post any comments, questions, suggestions or bugs in the comments.