A friend of mine has a stalker, and someone who keeps calling her house from a cell phone. Of course, she wants to know for sure if they are one and the same.
On her caller I.D., it shows up as <wireless service provider> and the number. Is there any way to take a cell number and track down the name under which it is registered?
If your friend is truly being stalked, call the police. They can retrieve billing records from the phone company or arrange a trace.
California has some nice stalker laws. What state is this? Are you sure they aren’t telemarketer calls?
Also, if they can see the number with caller ID, you don’t have to answer it.
Call both your friends and the stalkers phone companies too. Your friends company can trace the number and bar the calls. and the stalkers phone company will be have terms-of-service and will suspend the number.
If none of that works go to the police. None of this will necessarily reveal who is doing this tho’ unless he gets charged.
Just finished an eight + year stint in the telecom industry. My take:
Her caller ID won’t show a number because the cellphone call doesn’t start in the phone network. Even a trace from your phone company won’t be able to tell what phone number it comes from, in most areas. It will be able to tell what cell network the call came from.
Now the hard part. If your friend can convince the police, and through them a D.A. and a judge, that there’s a reasonable belief that these calls came from a stalker, they can subpoena the wireless carrier for subscriber info from this data. (From your friend’s phone number and the date/time of the calls, they will be able to determine from which number the call originated, and then from their billing records, the owner of that phone.) This may well end up requiring two subpoenas, as it’s possible that the primary carrier will show that number as having been sold to a reseller of their service … This is a long and involved process, and even to start it requires some kind of ‘reasonable suspicion’ to get the subpoena issued-a lawyer could tell you what kind of evidence would be required, but I sure can’t. 
What I can tell you for certain is that without the subpoena, you will not get anywhere with any wireless carriers. Any telecom company works under stringent regulations on releasing subscriber information-nobody at the cell phone service provider is going to give out information out of personal concern for the situation …
If she knows who the stalker is, it’s probably going to be easier to get a search warrant & go through his bills. But again, IANAL and know nothing whatsoever about criminal law, except for what I see on Law & Order.
If he’s using a prepaid service, you’ll never know. He may have purchased a phone and airtime without giving out any personal information.
Go live with ‘biker’ gang for a few weeks.
Get new Phone Number.
Go hide in closet.
Call cops.
Kill’em.