You can contact the police, but I would look for the same person you dealt with earlier. A restraining order is not worth much, unless the restrained person "gets the point" and stays away. If this customer is looking for real trouble, a piece of paper won't do much to deter him. Don't let the cops off the hook: if they revealed your name, make them help you.
If my answer has been helpful please note that. We answer these questions free of charge and appreciate the feedback.
Contact the police and the prosecutor's office. Good luck.
The response above is not intended as legal advice since it’s impracticable to provide thorough, accurate advice based upon the query without additional details. It is highly recommended that one should seek advice from a criminal defense attorney licensed in your jurisdiction by setting up a confidential meeting. Moreover, this response does not constitute the creation of an attorney-client relationship since this message is not a confidential communication because it was posted on a public website, thereby publicly disclosing the information, which is another reason to setup a confidential meeting with an attorney.
Local law enforcement is your best resource in this type of situation. If the local police are not "interested" then contact state authorities. Document that is write down everything noting the persons and dates of your contacts.
Please do NOT use this answer/response to say or do anything regarding your situation. This answer/response is based on the information provided in the question asked and requires a much more complete context than is available in this public forum. BEFORE you say or do anything consult with an experienced Federal and/or state criminal defense attorney in your jurisdiction who will listen to you and your concerns.