Well my g/f drives a Oldsmobile Intrigue and shes having some sort of rattle sound when accelerating which seems to be coming from the exhaust and am wondering what could be the issue?

Look under the car for any broken exhaust mounts and around the heat shield for the cat.

Probably a heat sheild for the cat, My friends Jetta had the same problem.

X2 and it was one of my friends Jetta's too.

If it is the heat shield can you get a replacement for those?

If it's the heat shields on the cat itself, you can use a couple of big stainless steel hose clamps around the cat to secure them. The heat shields usually break around the spot welds, and start rattling.

or it could be broken baffles in the muff, get under the car and have her give it some gas to check it out

Could be lots of things. You're gonna have to crawl around and look if you want to continue to receive the poon.