here's a link to a video i made {iphone}, looking under the car.
http://www.youtube.com/watch?v=pKqokTqz1Cw
i felt the back of the motor from the top, and the pass side head feels a little wet on the back, but not under the valve cover. possibly coming from the back of the intake. the ONLY thing that makes me think it isn't the oil pressure sending unit, is cause the oil that's leaking, is ALL OVER the underside of the car, not just the driver's side