They won't turn white in the winter unless you ride on salty roads, which I'll bet you don't.

Belt guard? That looks like black painted steel to me. You can't polish that out.

If you want to do it yourself, get yourself a buffer:

http://www.harborfreight.com/cpi/cta...emnumber=40668

Maybe a stand:


http://www.harborfreight.com/cpi/cta...temnumber=7769

A variety of wheels:
http://da.harborfreight.com/cpisearc...buffing+wheels

and some compound:

http://www.eastwoodco.com/jump.jsp?i...8&iSubCat=1480

Aluminum is not hard to do.