http://www.grandprixforums.net/f73/cable-on-window-regulator-comes-off-464.html
I can probably talk you through it, done it enough times. Is the motor itself not working, is the cable off the track but the motor still works or when you hit the switch nothing works at all.
Best thing to do is take off the door panel first to see what the problem is. You will need a set of 6 star screwdrivers or Autozone has a set that will hook onto your socket set. I suggest the socket set because it has about 10 different sizes.
To take the panel off you'll notice two caps under the door handle area. Carefully remove them and use a flashlight to see the screws inside then you'll know what I'm talking about when I say star screwdrivers (don't know the official name for them) the outside edges of the door panel have little plastic plugs that hold it tight to the door frame.
Once the panel is off there is a piece of plastic glued to the frame. As you pull it away from the door frame the glue will tend to stretch with it. Take your finger and break the string and restick it to the door. You'll need it there when you put the plastic back. Try to put it back on the existing glue to build up a mound. You'll see when you get there.
Then try the switch on the door to see what the problem is, motor or cable.
The motor is bolted to the door frame by 2 or three bolts. The cable runs from the black plastic housing on the motor to the window regulator. The window regulator is bolted to the door frame by 4 bolts and the window is bolted to the frame by two bolts. To get the window away from the frame lower it till you get access to the two bolts and then remove. Don't take the window out of the door, just push it back up and use duct tape to hold it all the way up.
If it's just the motor you can order one from Ed Morad and then replace. If its the cable loose because one of the plastic guides is off you can use the link above to dissasemble and order just the clip you need from Ed or order a new/used frame from Ed.
If you want just the motor or frame you can dissasemble the motor/frame from each other by removing 3 bolts that hold the black plastic housing to the motor. Be careful when you do this. put a screwdriver between the motor and housing to keep the white plastic sprocket inside the black plastic housing or you'll definitely need the link above.
Usually when a window goes out it's the cable getting stuck or misaligned in the black plastic housing or a guide has broken, you'll have to determine this yourself. If the motor doesn't work or the motor works but the cable is loose from the frame I'd suggest ordering a motor or frame from Ed before you take everything apart because trying to rig the window to stay up after you've taken everything apart is a pain till the new part arrives.
Any questions just PM me!