this has been discussed a few times.
search the forum.
there's links for utilities that will order the mp3s for you as you wish.
when i have time i'll try to dig up a few of those links.
One Ring to rule them all, One Ring to find them,
One Ring to bring them all and in the darkness bind them
In the land of Mordor, where the Shadows lie
M.C. Escher - Reptilien