Well all you need is the original song and a music editor.
1.Open the song in the editor and "loop" it.
2.Then save it ass an ogg file.
3.Make sure it isn't a full song when you finish.
4.Then put the song in your add-on's music folder.
You don't really need someone to "find it" as an add-on.
Mainly because it isn't considered an add-on, just a music loop.