What to clean/poilsh aluminum rims

Ok guys car has sat under the carport all winter and the once shiny rims have become dull. They are aluminum and I got them cause they looked good and biggest of all they dont RUST! but now that they have "dulled up" what is the best stuff to put a shine back on them...they dont need to shine like chrome or anything just want them clean and non tarnished looking. I have a drill a mothers power ball and some buffs/wheels and stuff I can use..just dont know what compound/stuff to use to clean them up. HELP please!