The hole for the drain? As far as the oil supply to the head it comes in at the front-left of the block (standing in front of your bumper looking at the motor. The oil then comes through the cylinder head above the valves, and from there goes to the oil distribution block. If I remember correctly there are "rails" that run down the length of the cylinder head where oil passages branch off and supply oil to the lifters and then the cam bearings.
The engine block is fairly straight forward. On the crank pulley side of the block you will find a hole where the oil comes in from the oil filter housing after it has been filtered and cooled. The main oil galley is a straight shot to the flywheel side of the block. You can see a hex socket head taper plug there where the hole was sealed after being bored during manufacture. Right around there that is where the oil branches to go to the cylinder head. There are branches along the whole length of this main oil galley to supply the main bearings.