[KimMG]

Pressurize the cooling system and find out exactly where the leak is coming from. You maybe able to rent a pressure tester from Autozone. It kind of looks like a bicycle pump. Headgaskets usually blow around the combustion chambers and if it is not the headgasket, then you will have done all that work for nothing.
Location of freeze plugs; Go to the dealer when they are not too busy and buy an oil filter, ask the parts person if there are any freeze plugs in the questionable area. The parts person maybe willing to print you out the diagram.
Also on some cars there is a water jacket in the intake manifold, check to see if your motor has one.
Auto parts stores also carry dyes that can be added to the cooling system help track down leaks.