Which VW model wheels will fit the 93 VW Corrado?
I want to buy vw wheels that will fit my Corrado, other than the
original factory wheels.

I would suggest some on-line tire and wheel stores. Here are two that
should help get you started:

http://www.tirerack.com 
They list 63 wheels for your '93 Corrado plus they show what they look
like on your car in color.

http://www.tires.com 
They have no original size 15" wheels but plenty of "+1" and "+2"
sizes. These refer to 1" and 2" larger diameter wheels when used with
lower profiles tires give you the same overall tire diameter as the
original 205/50-15 tires your car came with. I've upgraded a few of my
own cars over the years with +1 or +2 packages and found the handling
and looks greatly improved over the stock size.

Don't forget to check ebay motors (www.ebaymotors.com) for used and
new wheels. For your Corrado the selection might be hit or miss, but
you might find a good deal. I'm sure wheels for later model VWs like
the Golf or Jetta would fit but I don't have any good source for that
kind of fittment interchange info.

Good luck!

-- Kevin