Any process available to track/trace an incoming call on on a cell phone that shows up on the receiving cell phone as PRIVIATE or UNKNOWN?

By trace/track I am asking if the caller himself/herself can be identified. This question is related to threatening phone calls.

File a police report -- Ace

Now there is a service that makes it easy to find out the real number of a blocked and restricted calls. It does cost money ($5.00 per month to unmask numbers) to use with your cellphone.

For a little extra, you can even get the name and address of a blocked caller. Check it out. Hopefully it can help you.

Unblock restricted numbers using Trapcall's Bug, Mouse, or Bear Trap (http://www.horsebanger.com/spoofcard/unblock-restricted-numbers.html)