They won't take a report of your phone number being spoofed, but they'll deploy SWAT teams to unsuspecting houses at the word of bored teenagers.
Do you know the imposter's actual identity? What would you even report? If the perpetrator is international, what are your local police even supposed to do with this information?
You might have a little better luck with the FBI, but if you don't show up with hard evidence (i.e. do all the work for them), you won't get anywhere with them either.
All of this goes to show you why this sort of scheme remains successful. Nobody cares. Fraud is just an assumed risk.