I found this site awhile back, the owner sells polishing equipment: polishing compounds, buffing wheels, tools, etc. If you check out the "finishing forums" they are pretty much dominated by motorcyclists who polish their bike parts and there are tutorials on how to polish aluminum to a mirror finish and also more specific tutorials and tips on polishing bike parts and frames. Take a look around there is a lots of info.

Main Page
http://www.caswellplating.com/index.html

Forums
http://forum.caswellplating.com/

~JB