oil leak

Thanks to all the previous help on my 97 blazer LT. I have a moderate oil leak from front of engine. How do I diagnose where it comes from? It drips out from the plastic cover where the oil filter access panel is but it is so so damn oily I can't see where it's coming from. Any help is highly appreciated.

Power wash it, add some dye to the oil, get out the black light and find that the oil cooler lines are leaking, replace the oil cooler lines ;) (very common problem)