I received some disturbing calls this morning from an unknown number. Is there any way that I can get the number without going to the authorities?

No, and even then they will most likely not give you the number merely follow up on it

How doI stop or block private numbers

How do I stop or block private numbersCheck with your service provider - they should be able to tell you how. And report these calls to them. Is your number recently acquired? You may be receiving calls intended for the previous holder of what is now your number.

If you know who is calling you from private number call your company and place a block on that number