I've been looking into inoperable windows lately and it seems many people have had trouble from the switches having dirt and dust built up inside them. Some folks replace the switches and some take them apart and just clean. Usually it seems the symptoms of dirty switches are slow window operation or operation in one direction but not the other. Did your window just give out all of a suudden or was it gradual? If all of a sudden and it goes neither up or down then it may be something other than the switches. Unfortunately, I don't know any quick and easy methods for getting the window up.
-Chris