Transmission Computers are usually located on the transmission it self. but if not then a dealer ship or the main computer in the vehicle it self may operate the transmission.
The location for this particular device would be located under the hood of this vehicle. You can locate near the transmission, and it would normally be located under the device.
You question isn't very clear. If your asking where the computer that controls the transmission is located then it is the ecu. It controls the engine and the transmission both.