Ya grand ams 1999+ have to be programmed from the dealer or someone with the proper scan tool.
the RPO # is in the trunk on the spare tire lid, but good luck finding out which of them multiple codes are for the keyless entry. lol easier to call or visit a GM dealer and run the vin to check.
i guess you can also look in the underhood fuse boxes for the lock/unlock replays. if it doesnt have them then it prob dont have remote entry. but over 75% of GM cars come with the option tho might not come with the keyfob.
i liked the older models where you just used a jumper in the trunk to activate the programming features. guess thieves might have liked that too. lol
And welcome to AF gravytrain!
edit: here is a thread pertaining to GM keyfobs
http://www.automotiveforums.com/vbul...d.php?t=173306