1998 Cavalier Error code Help

I have a 1998 Cav with a shift problem, I pulled the codes and they show up as follows:

PO121 Throttle/Pedal position sensor/Switch A Circuit range/Performance Problem

and

PO122 Throttle/Pedal position sensor/Switch A Circuit low input

Can anyone tell me if "Throttle/Pedal position sensor" is the name I would give AutoZone or someone to get the sensor or is there a different name, and also where is it located on the vehicle?
Thanks in Advance
Chris