I have a 2000 Tahoe, keyfob #16245100-29. I need to purchase a second one but am looking for the instructions on programming it. Anyone have a link where I can get these? Thanks much

http://www.automotiveforums.com/vbulletin/showthread.php?t=129220&highlight=fob+programming

has the directions to reprogram.

http://www.gmpartsdirect.com
http://www.trademotion.com/partlocator/index.cfm?siteid=213815
http://www.rmsautoparts.com/

I got mine from the first website and found the others later but have not used them.

//2000CAYukon

Transmitter Programming
If they key is in the ON position during the programming procedure, the horn chirp will be disabled, if the key is in the OFF position, the horn chirp will be enabled. The horn will chirp when the lock button is pressed two times.

When reprogramming the remote control door lock reciever, All transmitters must be programmed at this time in order for the transmitters to operate the vehicle. Transmitters not programed at this time will not work and the procedure will have to be redone with all the transmitters.

Ground pin 4 to pin 8 of the data link connector (DLC). The receiver will respond by locking and unlocking the doors, and activating the liftgate window release (if equipped) within 2 seconds.
Press and hold the LOCK and UNLOCK buttons simultaneously on the first transmitter to be programmed until the locks cycle (approximately 10 seconds).
Repeat step 2 for up to four total transmitters to be programmed (if available). The receiver will respond by locking and unlocking the doors and activating the liftgate window release (if equipped) within 2 seconds.
Remove the ground applied to the DLC.
Lock and unlock the doors in order to verify the transmitter operation.
Activate the rear window release in order to verify the transmitter operation.