Last night, Joe sent us a GUI app he put together for Cleverboy's ringtone hack we posted yesterday. Ringtonator is a drag-and-drop application that will turn any AAC file into an iTunes/iPhone ringtone, or vice versa.
One caveat-- while this program doesn't require a separate install of AtomicParsley, the application that makes the metadata edit possible, it does still require AAC encoding on the sound file-- Joe says he might add in mp3 to AAC conversion at a later date, but he doesn't really have to, as it's easy enough to figure out how to do that.
But once you've got the AAC file, just drag it onto this little wrench phone thing, and iTunes (the current iteration, anyway) will play nice with it. Thanks, Joe!