I'm developing an web app where the customer will use pay pal to pay for screen savers. I want to make sure that they have arrived at my download page from the pay pal page.

Is there any way to check a visitor's web browser to see if it was just sent to the page from a paypal.com address? I.e... can I get the last url??? or something that will let me know where they came from?

Thanks....
Tom Gahagan