More than once I have looked for the ultimate solution to generating ASDocs, have tried ANT builds, third-party plugins etc. Little did i realise there was a much easier option, just use External Tools as outlined here. From what i can tell you can only document comments in .as files or inside the SCRIPT tag of an .mxml tag which is lame, however that all changes with FB4, bring it on!
So heres a few good links to get you up to speed, no more excuses!
ASDoc Tags
ASDoc commandline parameters
Common HTML tags supported by ASDoc
