You my have multiple problems.
If you have an intake manifold gasket leak, coolant is likely what is exiting the gasket. Your car is 22 years old. The coolant is mixing with the dirt and oil around the engine, making it look like oil. Are you loosing coolant?
Your loss of oil may be a separate issue. Dan pointed out valve cover gaskets. Are you burning oil?
In your troubleshooting, you may want to consider separating the oil usage from the intake gasket. On my 98 4.3L S10, I had a intake manifold gasket leak, and a radiator leak at the same time. Multiple failures can show at the same time.
2001 Bonneville SSEi, 219,000 miles.
Whats in my driveway:
1998 Chevy S10 4x4 ZR2, 1999 Olds Bravada, 2001 Pontiac Bonneville SSEi, 2007 Ford F-350 regular cab 2WD, 2008 BMW 335i coupe (Wife'* replacement for her Bonneville). The Bonneville is my favorite of all the cars in the driveway.