I think I have exactly the same leak...mine is on the driver's side. Crawled under the car, couldn't see anything at first, then noticed an oil drop up by the back of the engine...probably the valve cover.
From above, I can't seem to figure out how to get the engine cover off. The front section is easy enough but the back part must have some hidden clamps or something! How did you do it?
Also, was replacing the grommet (cam plug) easy enough? i.e. is it simply a screw off-screw on process?
THANKS for any help you can give me!!!