If there's a chance it might be a genuine charge, you can look up the regstered address of any limited company. There's an A.S. Limited, registered at an accountant's office in Coventry, registration number 04448235. You could try contacting them at their registered office but the chances are that they wont know any details unless you get through to the sales or accounts department.
If you are sure that it's not genuine, just call your bank and tell them. The should be able to say how/if the transaction was authorised. They may ask you to sign something but they should reverse an unauthorised or improperly authorised charge for you without too much fuss.