Just out of curiosity, how does a cellco log a spoofed call? I can put any number in so it looks like it might be a friend on your caller ID but I'm not really calling from that number. Wouldn't the actual phone used be listed in the carrier's log? If you don't answer and it doesn't go to voicemail would it still be there? In that case, you would need the time of the call.
You can do a whois or another lookup for email headers, but the only ones I've found close is to type in the phone number that appears in 800 notes then block the number.
I've seen some rumblings about carriers getting the nod to ban junk calls, and the baddies might be looking for ways around it.
I get loads of calls from Verizon numbers, and I don't know anyone that uses their service. My numbers were ported to another carrier. Years ago I got fake faxes logged to our fax machine's line.. The numbers were never charged on our fax bill. Spam caller using our number as a scam of some sort.