Valve Cover Leaking Oil

I have a 97 Lumina 3.1 I've noticed when the car is parked on a incline with the front higher than rear, there's small puddles in my driveway. When I park with the front lower no puddles. Looking at the engine, it appears to be leaking from under the front valve cover. My question is:

Would it be allright to tighten valve cover bolts or will this warp covers and cause more of a leak??

Thanks in Advance

Just replace the gaskets. Its kinda hard to warp aluminum valve covers without breaking them first.
The leak though, is propably your oil pan gasket. Make sure the bolts are tight on the back side of it.