Did you (whoever built the engine) use the supplied rubber gaskets for the block ends? If so, you may want to remove them and use a nice bead of Silicone Gasket maker for those, and tie into the intake gaskets as well. Those rubber gaskets like to leak badly. Just be sure NOT to use anything on the actual intake gasket whether intake side or head side and you should be good to go.
They are gaskets under your valve covers that keep oil from leaking out.
I'm assuming your grand am has a 3400 v6 which are known for intake and head gaskets leaking. so its possible that one of those gaskets are leaking so bad that coolant is leaking from intake/heads down onto your valvetrain and then down into your oil pan. more than likely its your intake gaskets leaking.
take the exhaust manifolds to a machine shop ask to have the mating surface that contacts the cylinder head to be machined ,phone a shop and they will know what this means usually 45 a manifold
Heads do not have to be ground because they are aluminum. If you're taking both heads off then you need 2 new gaskets. It's not a bad Idea to replace both if one is leaking though because the other one might not be far behind.
If a transmission is leaking fluid, it is likely that a seal or gasket has failed. Replace the gaskets and seals and the leaking should stop.
Could be the intake manifold gaskets are leaking.
Leaking valve cover gaskets?
Rubber gaskets are used as seals between two objects, like a lid to a jar. Usually, rubber gaskets are used to prevent something from leaking. http://en.wikipedia.org/wiki/Gasket
Could be a couple things, best case is your valve covers gaskets are bad, and worst case is your intake is leaking.
Not unless it is leaking so badly as to get enough oil on the plug wires to short them out.
your heater core is leaking
check your radiator hoses and change gaskets