send in to their site a request for a domain name, give a bit of false info obout your credit card number _wrong number) and a correct reply address.
That should make them generate an answer - eager to take more vcash off of you, and then reply to the number / address with your question of.............!
Get involved with the trading standards council as it seems that you may have been ripped off!
Search online about the company and see if that generates a mail / email address!
contact your credit card company and ask if they can help (especially if you have a gold or platinum card), they may be able and willing to look into cases of this nature.
get in touch with your local police office and see if there is anything that they can do to help.... it seems as though you may heve been 'mugged' in an electronic way!
Just a few suggestions for you (!).
Hope this gets some sort of closure for you!
Good luck and be persistant..... after all it is your money!