What happened to the cops?

well they were dead

You can even hear a radio news broadcast mentioning that the "biggest manhunt in US law enforcement history was under way". Yet there's not a cop in sight for the rest of the movie. Where were they hunting him? Aruba?

They died.

It was fascinating to me, though none of the Terminator movies seemed to touch this, but what would happen if the authorities did all come to recognize that an evil unstoppable cyborg from the future was out to kill a woman and did whatever they could to stop him? It would essentially have turned into a Godzilla movie at that point with the military putting together all manner of traps and weapons to destroy him. I imagine a Terminator would not do too well if lured in to a pit-fall trap (how much would they have weighed anyway?) and could have been killed or badly damaged by rockets, bazookas, recoiless rifles, tank shells, or even just really large high-explosive detonations. The movies never quite get into why the terminators are so invincible. Maybe the skeleton is like diamond-coated space titanium or whatever, but there's all kinds of weak areas like connections, sensors, etc which would be easily damaged before the rest of the structure.

They waited until T3 and tried to stop him at the cemetery.