often when you buy things "especially from "free" places like VistaPrint, even from big store chain office supply stores that have online web sites and even places like priceline.com I have had to remove some software from a machine once that was charging his credit card every month, they tie themselves into these rebate and "cash back/money back " money leeches. "You have earned a $10 cash reward" they say.
if you read carefully, you will notice somewhere it says "if you agree, your credit card will be charged a membership fee of $14.95/mo" (or whatever amount). There's the rub. You get $10 (or whatever amount) in cash back now, but your credit card is going to be charged a monthly rate, thereby infinitely outdebiting your little credit and causing an seemingly unending woe.
Once you have started it, How do you stop it? If it is purely software, it can be removed by someone who is a Software Engineer and has written ActiveX controls (the usual delivery method) and knows their way around regedit. If it is an ACH transaction, I don't know of any remedy except maybe taking it up with your bank. If it is not an ACH transaction by the bank, then it is most likely software doing it, and you have to find a way to stop the software from charging you. trace it to the source. take down names and numbers, registry keys, bank transaction numbers, anything you can get your hands on that will help you in your quest. So far I have not found one of these companies providing a phone number or any contact info, but if you do sign up for one, DO TAKE DOWN THEIR CONTACT INFO (print it out and keep it)! Usually they will say they are not affiliated with the company that is providing these offers. You can probably track them down in detail through your bank. the bank has lots of info on every transaction the problem is extracting that info from them.