Very clever. That will get you banned, all right. But it may not stop AOL from billing you forever. I'd love to hear a clever way to stop them from doing that!
Not all that hard. If you have a zero balance on the credit card they bill you on, just cancel the card. I had to do that to keep MSN from billing me after I terminated my account with them in 1998.
Call your credit card company or local bank (depending on how you're being billed) and inform them the charges are fraudulent. They're required by law to remove them immediately and deal with the company themselves.
You should then also file a complaint with your state's Attorney General's office, as well as Virginia's (where AOL is headquartered). You could even file a lawsuit, if you had the time, money and inclination.