Here is a nice bathtub caulking video (opens in new window)
about how to caulk your bathtub after it is refinished. You won't
have to worry about the part about cleaning out the old caulk because
that will have been removed during the bathtub refinishing process. I
recommend using a "high gloss" tub and tile caulk which will blend
in better on the refinished surface and be easier to keep clean.
One good brand is POLYSEAMSEAL® TUB & TILE ULTRA (available