hit the door panel right next to the speaker with your fist. Hit it hard, trust me. I can't take credit for this though, learned it from another site. Saved me a repair bill though, so at least try it prior to taking it to the shop. Worked for me.
my driver side window wasn't working for a long time (a year or so) using the switch on the panel. one day i used the function on my key to unlock and open windows by pressing and holding down the unlock button, and my window rolled down! since then, it works fine.