That means it was a good stealth install .
Its control unit is probably under your dash. Since it has a remote start, try tracing the ignition wires under the dash. the12volt.com should have your vehicle wiring info. Also if you have an LED mounted somewhere, start by tracing the wires behind it.

Once you find the control unit, you should be able to trace the valet switch. It might be mounted near the hood release lever.