When you say you suspect this, what makes you suspect a blown head gasket? If you are talking about a 3.8, especially 94-98, then chances are, the gasket is bad. In the 3.8, most likely one of the two front cylinders.
A blown head gasket can manifest itself many different ways - most commonly a coolant leaks into a cylinder. Signs of this would be White Smoke out the tailpipe in extreme cases, loss of compression, loss of coolant with no extrenal leak, extremely clean (steam-cleaned) spark plug from the affetced cylinder.
You could also lose oil either into the engine or externally. This will not last long, and the ticking noise from the offending side's valvetrain will become increasingly annoying.
To find a blown gasket, and zero in on the cause will take a few steps. First, a compression test will tell you that there is a problem. (Be wary of two side-by-side cylinders with the exact same compression - could blow the gasket between two cylinders.) When you do the compression test, look at tyour plugs - if they are wet, look extremely clean, or even have oil fouling, indicate problems.
A leak down test will narrow it down and tell you where it is leaking - like was said above, listen for hiss in valve covers, exhaust, bubbles in radiator, etc.
If you get bubbles into the radiator, do a pressure test on the cooling system and see if it will hold pressure. If will not hold, and you cannot find any external leaks, probably the head gasket. I have seen blown gasket that would hold cooling pressure when cold, but leak when cold, though.
Lastly, go to a parts store and get a chemical test to verify the head gasket is leaking inot the cooling system.