On the left will be the account number, underneath it will be the number of the reporting company (identifier) at the end of your credit report will be a list of reporting companies and then inquiring companies, there you will have your contact information. With Dr.s be wary, they will submit to your insurance and bill you anyway, double billing, and the amounts are usually small enough that you will just pay it rather than dispute it, and they win again. They also own most of their own collection agencies. The Dr. that owned the office building where my office was located in La Plata was raided by the FBI, his patients miraculously appeared at each of his 10 offices, even those that were just parking lots! Of course he left to start a practice in Iraq...