What do you need to know?

Woodworking forum is a good bet, but you can find some good experience here too.

KarinL

Thanks, I'll try the woodworking forum too. I want to know how to tell what kind of finish is on an old table as I'd like to add a few coats to make it water resistant.

To tell what the old finish is....you find out what dissolves it. If it's lacquer it will dissolve in lacquer thinner, if it's shellac it will dissolve in alcohol I not the rubbing kind) if it's varnish it will dissolve a bit in lacquer thinner....but more slowly.
But if it's an old finish it doesn't matter what you put over the top....I would get some oil based polyurethane.
Linda C