It's not the Nigerian scam - like most I have come across that all too often! What I have actually found is someone who is offering credit card numbers and tools to spoof credit cards online. Very unsavoury!
that the UK Police prefer that you do not report Internet related crime to them directly. This is because they are inundated with reports about matters over which they can take no action - usually because the sites in question are located on servers in other countries - or because in fact no crime is being/has been committed.
There is an organisation called the Internet Watch Foundation that was set up in conjunction with the Police and major Internet service providers, and the Police would prefer that you refer all instances of suspected Internet crime to this source intitially. The IWF have people who are specifically trained to be able to decide whether or not your report should be passed to Police or not, and they will take it from there.