What kind of civil lawyer do I need to look for a security co. (i.e. like Brinks) who is trying to sue me?

This company is trying to sue me for something that was already paid for. Their "big company" bought the contract from them. I was released from my contract with their "big company", because the company who is trying to sue me falsified a doent stating I was the owner of the home. I provided the falsified doent to this company's attorney, but they still want to go into litigation (and by the way they changed the charges too after I called them out of what they did not do...is this ethical?). So, this company is trying to sue me for something that is already closed. I need help with finding what type of civil lawyer would I need to look up.