[masraum]

Stop using a debit card and switch to a credit card that you pay and use just as you would the debit card.

I suspect killing the cvv2 on the back would help since many/most sites require it these days, but not all sites do. It would probably cut way down on your issues, but may not stop them. Heck, even just putting a little paint on top of the cvv2. Then they would have to scrape it off and if you got the card back with the paint removed, you'd know that someone was up to no good.