Monetizing single page or post

Hi all, i′ve been stuck on this one for a few days, finally came back here and see if I get some help. Im a newbie so please be specific, =).

Im trying to “sell” one-time access to a page withing my wordpress installation. What I mean is, you pay with a button, and you get access one time only to a certain page. The only way for someone (who has already paid) to access again, would be to buy again.

This page must be unaccessable for anyone who hasn′t paid (I havent been able to accomplish this with paypal, no idea why).

Im willing to pay a tiny amount if someone comes up with a plugin or two. If you take donations, be certain to get mine. I dont have money, but i′m desperate, =P.

Maybe theres already a plugin im missing???

Thanks on advanced =) good luck.