unfortuanly the amount is too small to actually get any justice on them, it is also too small to get a claim back via the credit card or bank.
http://www.consumerdirect.gov.uk/after_you_buy/online_shopping/your-rights/

What i would do is put all of the info on here (or email me it) and then we can investigate, find the ISP and maybe IP of the user who took the money, try and sort it out that way. Or find the bank that the money was transacted to.