Don't mess with the blue people. Years back I had one call over, and over, I found out who they where, and their address after a while of searching.
They called, and I told them I was going to come cut their phone line, and then follow them home, and burn their house down with them in it.
They never called again.
A car dealer kept calling ones, and sending me ads, I had to threaten them.
Sad thing is now they use computer spoofing, you can't find them, and usually they are in another country.