Internal FM transmitter APP? An internal FM transmitter would have to be hardware based, and the MOTO Droid doesn't have it. All Radio APPS are internet based streaming applications. Each has it's own set of supported streams based on where they are picking up the base from.
Once we have Flash, we should be able to play from the browser at Radiotime.com. They have the most comprehensive list of stations that I have seen. There is also an APP that points to radiotime that is being developed for the Android OS. I have posted that in other threads, but the APP is WunderRadio.