How do I get my windshield replaced on a GEM 2002 e825 4 seater?

I just purchased a 2002 GEM car (4 seater) that needs a new windshield. I have no idea where to start. Can anyone give me some advice? I also need to replace the seat belts as well as the part of the front seats that attaches it to the car and lets it slide back and forth. I got the cart cheap, but it was at the beach and most of the exposed metal is rusted. Can anyone tell me the best place to buy these kinds of parts for the car? Thanks in advance for your help.

A good start is to have parts and service manuals for the GEM. A dealer in Miami has links to download parts and service manuals for various model years.