depending how clever the person was a phone call can be generated from a computer and bounced through several VOIP servers and be pretty impossible to track down, at least for anyone short of the NSA... County Mounties won't have the resources to deal with it.
This has happened often enough so that some vengeful screw-up MUST have been caught by now.
I would never alert the cops, but it would be better for the perp if the cops caught him before I did.
I’m a firm believer in using a bat in such situations, so as not to put anybody’s 2A rights at risk.