Gone for a while, another big problem

[SteelMohawk]

My truck's temp gauge has been reading hot for about a week now, maybe more, but it was in the shop for a while, and I think it started "overheating" before then. I made sure there were always liquid in it, and it didn't seem to lose much if any coolant. That was until last night.
I had to drive about 2 hours roundtrip yesterday, and couldnt get an alternate vehicle. when I got to my destination, I heard boiling/bubbly coolant sound. It was strange though because my temp guage wasn't as high as it normally was. Anyways I put some more coolant, because it finally started losing a fair amount(.5 to 1 gallon) of coolant. on the ride home I knew it was going to be a headache. about 10 miles from home I heard a pop(pretty sure it was my temp guage which I found later to be destroyed) and luckily as it stalled out, I was only a little walk from a 7-11 which sells coolant. I needed a lot as it all was sprayed over the front quarter panels and inside of my engine compartment.

I originally thought this problem was going to be my water pump. THis morning I go out, put about 1.5 gallons of coolant in it started it up, to look for leaks. It started, and was ok the first time. I shut it off and my spill over resvervoir was filling up, again with lots of air(i think) in the process. I dumped that reservoir because it was dirty(i think it was from the resevoir as much as anything. I squeezed the radiator hoses, and started seeing some leaking from the front of the engine, and at one of the hose/radiator links. When I started it again, for the first time today the exhaust manifold were steaming. Obviously fluid(coolant) is hitting the exhaust manifolds. Is this a tell-tale sign of a blown head gasket? if so how do I check for a cracked head, if i decide to do this myself? I would really like to do it myself after just spending $900 in the shop. and missing the best month of the year without my toy.