If its the upper intake manifold its a simple job, just make sure to replace the gaskets.. its litterly a few screws, and disconect the egr "carefully", also note there's a gasket there too.. I have a 07, and this past month I must of removed and installed it about a 100 times just trying to trinkets shot my mis-fires.
Step by step removal...cliff notes version:
1. Remove your intake hose connected @ the trottle body.
2. Disconnect any vacuum lines tuning to intake manifold.
3. It should be a 8 or 10 mm screw (about 8 of them) to unscrew.
4. Disconnect EGR , be 2 screws holding it in place to the intake manifold. ( watch for gasket, falls telltale easily)
5. Disconnect any wire harness clips attached to the intake manifold.
6. Check if all is dissconnected, and remove.
Follow steps in reverse for install, just be sure to replace your gaskets. And clean and junk around the intakemanifold with paper towel, just to get rid of any old gunk and such. Hope this helps..
FYI @ our shop. (auto-modifications) It would cost about $150(+ part). Depending on what needs to be done. Now since your just replacing I suggest shop around for the best deal..eBay, rockauto.com, Google shopper, etc. Trust me with good scouting you'll be able to pick it up for a fairly decent price