Exact same thing happened to my T/A about two weeks ago (passenger side). I ordered the regulator and motor assembly from rock auto for about $69 plus shipping. About half the cost of the part stores, and I was able to replace both units to save future hassle.
edit: Also, thanks to the advice from others on this forum, I replaced the motor/regulator with Dorman brand parts. Supposedly Dorman makes their motors new vice refurbishing old ones. As an added bonus, my window now raises/lowers twice as fast as stock! No more slow window!
1999 Pontiac Trans Am (T56)
1999 Buick Regal LS (sold)
1991 Chevrolet Camaro RS (305/5spd) (sold)
1990 Chevrolet Camaro RS (305/5spd) (sold)
Last edited by FinallymyT/A; 07-07-2012 at 10:33 PM.
Reason: add manufacturer details