96 - Driver Door Rattling Noise

At hignway speeds, the driver's door has a really annoying rattling sound. Taking the door panel off doesn't reveal anything obvious. Any suggestions?

Are any of the screws stripped?
Also.....I had the track for the window....fall right off....and that was a nasty rattle.....it was laying in the bottom of the inside of the door.
It is just tack welded in place.