Sadly I suspect even with a long list of people who have been ripped off the police response is likely to be underwhelming at best.
Apologies if you have tried all of these:
How did you pay the £200? If via paypal, have you raised a complaint with them? I know other people on this thread have tried unsuccessfully but you should at least try. If via credit card either direct or via paypal, have you contacted your card company for a charge back?
Other than that, what about the government run MoneyClaim online:
Welcome to Money Claim Online
Making an online court claim for money : Directgov - Money, tax and benefits
It costs £30 (AIUI you can claim this from the debtor as well if you are successful) and if he ignores it you can then take further action. There may be debt collection agencies who can help, just make sure you read the small print and don't leave yourself liable to any charges.
Finally a lot of home insurance policies include a free legal helpline. There is also Trading Standards and Citizens advice Bureau