Where is the factory amp located on 2000 celica gts?

I dont think there is a factory amp in your car i might be wrong but, if it is aftermarket check under seats, or behind glove box beside computer... according to the wiring schematic i have it said different ...notice were is states location of amp and trigger.
2000 Toyota Celica Car Stereo Radio Wiring Diagram
Car Radio Constant 12v+ Wire: Blue/Yellow
Car Radio Switched 12v+ Wire: Gray
Car Radio Ground Wire: Brown
Car Radio Illumination Wire: N/A
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger: Black
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Front Speakers Size: N/A
Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Pink
Left Front Speaker Negative Wire (-): Violet
Right Front Speaker Positive Wire (+): Light Green
Right Front Speaker Negative Wire (-): Blue
Rear Speakers Size: N/A
Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Black
Left Rear Speaker Negative Wire (-): Yellow
Right Rear Speaker Positive Wire (+): Red
Right Rear Speaker Negative Wire (-): White