A lot of people swear by Simichrome. I bought a kit (
http://www.nakidparts.com/id41.html) recently that included a 4 inch mushroom shaped buffing pad on a drill adapter, two types of metal polish in a bar shape for use on stainless steel, and a container of Simichrome. Unfortunately I didn't have time to try it before leaving for the UCP show.
But I have used Simichrome before to polish up the finish on some guns and it seems to work very well.