If you're sure it's the switch, you'll have to replace the whole switch module. Some people have had limited success by taking it apart and cleaning it.
However, the majority of window problems on the Buick are actually bad window regulators.
Here's a link that shows how to replace one.
http://free-auto-repair-advice.blogspot.com/2007/10/replace-power-window-motor-regulator.html
On the drivers door armrest has the window lock switch been pressed on the left side ? If it has , then only the drivers door switches operate the power windows . Press the right side of the window lock switch
Many vehicles with power windows have a switch on the drivers side window control panel that can lock out control from all other switches, check to be sure that switch isn't on.
How to repair electric windows depends on what is wrong with them. If the motor that runs the window has burned out then replace the motor. If the switch is faulty then replace the switch. Check for broken wires, repair them if found.
I found that there is a normal and lock switch on drivers door and lock stops use of the windows.
broken switch or fuze
more than likely you will have to replace the drivers side master switch
It's probably a loose connection, but it might be the switch.
REMOVE AND REPLACE SWITCH AND CRIMP THE CONNECTOR TO THE SWITCH.
If your windows still work on the switch than it is most likely that the switch is bad I had the same problem with mine and it was the switch
Because the master control on the drivers door has separate areas for all windows. Start by checking power feeds at the drivers door switch.
If the fuse went out, NONE of the windows would work. I suspect the master switch on the drivers door panel. To confirm this, try the windows using the switch in the door for that window. If the windows work, the problem is the switch on the drivers door. If they don't, you've either got 4 bad motors or some loose wiring. Good luck.
Sounds like a defective switch on the driver's door disconnected wires on either door or you have a lock out switch turned on... with driver door, i suggest pulling your "panel" off and verify your switch is actually connected and if it is, then replace the switch