Debited Bank without permission

On 4/12/13, this company debited 30.00 from my account without authorization and 30.00 again on 5/16/13. I don't know where this company is located or their address. They are very clever to keep that a secret. The phone number on the check draft is 775-200-1525; unfortunately no one answers the phone or returns calls. My bank said that they can't put a stop check on their check because the check number is different each time. My bank has done little to help me resolve the fraudulent behavior of the above stated company!