Had ringtone set to original song. Found I had lost the Droid tones. Wanted them back - not lost.
Deleted Dolphin Browser. Quickuninstaller (Free). Cleared cache of many large programs (sorted by size). Suddenly the Droid ringtone / notification files appeared. Chose "Droid" as notification. Powered down then up. Loud / clear = Droid!!
Still can go to Music Player and select song as ringtone. Now, when I do this, the song is listed in the ringtone list along with the Droid ringtones. Can even change notification: Whatever is now selected will sound when Droid powers up.