If you report a harassing phone call from a private blocked caller to the phone company, it won't trace the call and the numbers for you. The law restricts telephone companies from releasing private phone numbers because this is against the privacy law. The only way to trace a number if you're getting abusive calls is to do things the legal way. Tracing blocked calls takes time and a lot of effort, but it can be done.
Try returning the call first. Usually the code *69 can be used as the first step to trace blocked calls. This automatically calls the person back so you will know the unknown caller. This may work in certain areas and with certain phone companies only.
Write a letter of complaint. State the instances in which the caller has been harassing you and explain how this has affected you. Provide as much information as you can in order to facilitate the process of tracing phone calls.
Give a letter dof complaint to the police detailing your desire to trace the blocked calls; try to get an order of protection. Make sure you have a lawful reason for tracing the phone calls. If the caller has been harassing you or disturbing you in any way, the police will inform your telephone company so it can start monitoring your calls. However, it still might not give the identity of the caller.
Get a lawyer to subpoena the number from the phone company. The lawyer will write to the company, asking it to pull the necessary information due to security and other reasons. Many times legal representation helps speed things along when tracking blocked calls.
Wait for the company to pull the information for you.
If you don't want to receive the private calls, you can block them. Ask your telephone company for this service. Women can prevent being targeted by obscene calls by listing their first initial and last name in the phone directory. Another option is having an unlisted number.
Law enforcement officials and the phone company may never track down the unknown caller if he uses multiple phone lines. The better option is to change your number.