Jim, unless theres a serious crack in the block, there's not many places at the front of the engine where the oil can come from.
The fuel pump to block gasket is the easiest choice. The gasket is cheap and theres only a couple bolts to remove to replace it. It's possible the combination pump has an internal leak, doubtful but check your oil for gas smell. Also monitor to make sure the oil level isn't rising. I only mention these as something to check for as I wouldn't put them high on the suspect list, atleast not until you rule out all the easy and obvious causes.
You mentioned the valve cover wasn't leaking but didn't specify if the side cover isn't, that would be my 2nd check.
Good luck
Dave
