Just had the identical problem with my wife's Saturn SC-2, and it was the cam cover gasket. On the Saturn, at least, the part was fairly inexpensive (about $35) and it was a very simple job, but as 7999 said, it's critical to get the mating surfaces clean (use "brake clean" spray to clean the oil and residue off). On the Saturn the cover is plastic "composite" so the bolt torquing is very low to keep the plastic from cracking (89 inch-pounds, which seemed not much more than finger-tight). Not sure if the Contour's cover is plastic or metal but if it's the former, be careful if you try to tighten the bolts first to see if you can stop the leak that way.
