2006 Chevy Aveo NOT covered under warranty

The shifter locks up in the park position, wont release unless you press the release button. The key wont come out of the ignition unless I unplug the battery.

I took it to a cheap mechanic ( tiss all I can afford ) he told me I needed to replace a switch the goes on or above the break pedal that controls the brake lights and unlocks the shifter when the brake is pressed.

Ive been doing Research online and found a Chevy Service Bulletin for the 2004-2006 Aveos:

Bulletin No.: 07-07-30-007

Date: April 04, 2007

TECHNICAL

Subject:
Automatic Transaxle/Transmission Shift Lever May Not Shift Out of Park (Replace Brake Transaxle Shift Interlock (BTSI) Solenoid)


Models:
2004-2006 Chevrolet Aveo
2004-2007 Chevrolet Optra (Canada Only)
2005-2006 Pontiac Wave (Canada Only)


Condition

Some customers may comment on either of the following conditions:

The automatic transaxle shift lever may not shift out of the park position and the ignition key cannot be removed (North American vehicles only).


The automatic transaxle shift lever may not shift out of the park position (vehicles outside of North America only).

Correction

Replace the brake transaxle shift interlock (BTSI) solenoid. Refer to Shift Lock Solenoid/Switch Assembly Replacement in SI.

I tried to buy the part at the Chevy dealer, but they cannot find the part! Nor can they hint on what else it might be.

So I guess what im asking is if it could be something else OR if someone can please give me a GM part number for the solenoid and where exactly it is located.

Thanks in advance for the help!