How to polish a steel bike?

[Trek420]

We've had two bikes powder coated and in both cases my LBS had them sandblasted and smoothed first.

Sandblasting's self explanatory, strip the bike and sand blast. Could you get equal results by laboriously using steel wool? Dunno.

He explained then they:
1) carefully check it for rust of course then ...
2) Check for dents, dings, scratches. They fill those. Don't quote me I think they used copper. Some kind of metal. They fill the dent then roll it down using a weighted tube to level consistent with the tube. If they have to do it several times to make it perfect they do. Why? Because stripped whether painted or clear coat those dings just stand out.

The result almost mirror like surface. Here's one he did (BTW no longer for sale):

http://forums.teamestrogen.com/showthread.php?t=23135