My 04 Grand Prix came with just one remote. I'd really like to get another one, but don't want to spend a lot. Whats the best way I can get another one? Do I have more than one option?

Probably get one from eBay, I've seen them for around +/-$20. You'll either have to take it to a dealer or find a locksmith with the proper scan/program tool(s) in order to program it to work with your car.

Is that what you have to do to the newer cars? I have gotten the remotes of ebay with installation instructions.

Is that what you have to do to the newer cars? I have gotten the remotes of ebay with installation instructions.

Irrelevant in this case. The '04 and up Grand Prixs with RKE require programming with a GM Tech II scan tool.