One of the best ways to combat fraud in the UK is to use CV2 / AVS checks and also use VBV and Mastercard.

I use all of these and have also stopped accepting PayPal and we get almost no fraudulent transactions now. Some people say that not accepting PayPal makes people not buy from you - This is a small price to pay to get rid of all the fraud. In my opinion fraudulent transactions through PayPal are getting worse.

Hope this helps.

Kind Regards