Yes, a repo man can GPS your car. Here's how it works:
The repo man will put a GPS tracker on your car. This tracker will allow the repo man to find your car no matter where it is.
If you're trying to avoid the repo man, you'll need to find a way to remove the tracker from your car. This is usually difficult to do, and it's not something that most people can do on their own.
If you're having trouble making your car payments, you should talk to your lender about your options. Repossession should be a last resort, and there may be other options available to you.