There has been a little discussion on how people can't find Grand Prix's in Junk yards and such, well here is how I do it, sometimes these places will also ship, you have to CALL THEM, DO NOT EMAIL THEM. They almost never respond to emails.
Car-Part.com--Used Auto Parts Market
Enter your year, Search for Pontiac Grand Prix and then search for any generic part (IE lets look for vent rings, so 2006 Grand Prix Dash). Enter your Zip code and SEARCH. Sometimes you'll get an option to cross reference years, so you can add info to the search inquiry. One you get the List of places and such, over in the top right column, hit Distance, this will sort Grand Prix's by distance from you, starting with the ones closest to you.
Sometimes you are lucky and they are pretty close and sometimes not, check back once a week usually as new things come up. Like I said above sometimes they will ship and sometimes not, but you HAVE TO CALL THEM. They almost never respond to emails.
Happy Hunting
Or just talk to KFish