Politics may not be everyone's favourite subject, but the only way to get something done here is to dabble in the system.
As jo90 says, this needs a change of the Law. Oople might be great, but it doesn't register on the law-making Ricther scale! You need to write to your MP. Go here...
http://www.parliament.uk/business/commons/
...and enter your postcode. Click on your MPs name and get their e-mail address. Send them an e-mail pointing out that being named as a guarantor and taking money from someone's bank account without permission is fraud, and against the Law. Ask what they are going to do about it. Ask where the Police are in this. Demand action! It will take no more time than putting a post on here.
If you don't get a reply, send a copy of the e-mail to the local paper asking why your MP is not interested in your issue. Nothing is going to happen until we make a fuss because it doesn't affect them, it affects us.
This will probably fall on deaf ears, but things aren't going to change if you post on here!!