The power window assembly for the 2000 Buick is an electric motor connected to a cable and capstan that raises and lowers the window via linkages for lack of a better term. From experience the motor doesn't usually go bad, it is the window cable capstan wears because it's plastic and the cable is steel. If you're handy you can get the assembly from the web and replace it for $50-$60. If not take it in and have the pros do it.
On the upper firewall on the driver's side
Go to your local junkyard and they allow you to search those vehicles for matching parts.
It's not on a track, the 1999 Regal windows have cables, therefore, you will have to replace the window motor.
at the bottom of the radiator on the driver's side.
Complete instructions with photos:
Buick Regal was created in 1973.
Freon valve on my 1989 Buick Regal Custom 3.1 V-6 located on driver side under the area of battery tray. Hope this helps!
P0410 2002 buick regal
which fuze controls the air in a buick regal
Master cylinder, upper firewall, driver's side.
On the driver`s side under the steering wheel to the left
4" in dash 4x6" in door and 6x9" in the back window