www.thedirectory.org
Caller ID means nothing in most cases.
See http://www.fakecaller.com/
I’ve encountered fake Caller ID data many times prior.
If the service is supported, *57 (or perhaps 1157, aka ‘call trace’...the phone company can allegedly trace all non-VOIP calls; look up how to do it with your regional carrier; the code is only part of it) is the most you can hope for without just getting them to stop calling (my method involves wasting their time lots of cursing...”Hang up, don’t call back” yelled every time they speak, interspersed with expletives...very effective. When they terminate the call, it usually gets removed from their system. Force them to terminate the call.).
I used that link a lot in the past. I’ve been getting calls on my cell from 215/278-xxxx a lot for the past month or so. Robocall from Philadelphia.
One of the reasons not to answer a phone if you don’t recognize the number is that if you answer, the caller knows it’s a viable number and suddenly charges will appear for calls to places you’ve never heard of.
It’s ridiculous that we have to go to such great lengths to protect ourselves. The old eight party line we had as a child was a lot more secure than what we have now.