If you are looking to make a cheap polishing wheel use an angle grinder. I shit you not. I used one and got excellent results. What you do is get and angle grinder and some metal straps similar to those used in toliet tanks that connect the lever to the bottom dealy thing. Anyway, bend the straps (3 or 4) over the grinder and make sure its secure. My 4.5 in ryobi special does just the trick and cost me $35. Buy some 6 inch polishing pads... Buy one sisal wheel and use brown tripoli with it after you have sanded it to with about 1000-1500 grain working your way from 400 or so making sure all your scratches are out from sanding it previously. Then after using the sisal wheel and tripoli use a loose cotton wheel with white compound to get that extra gleem! It'll take you a while but its worth the reward...
all of this is available at any home depot!