Depending on where you live, there are a number of shops from coast to coast that offer generic dyno testing and tuning, as well as many that are MOPAR-specific shops.
You can either do a Google search for dyno shops near you, or join one of the many charger forums and ask for opinions from guys who've actually gone to those shops.
your local dodge dealer carries it.
Your local Dodge dealer would be a good place to start...
Accessories for a Dodge Charger can be purchased at Dodge dealerships, car shops, WalMart, or online through sites like Amazon and local Craigslist sites.
your local chrysler dealer.
The best place to find a 2009 Dodge Charger is your local car dealership. The best place to find your local car dealership is to check in your local telephone directory.
Try your local Dodge dealers parts man.
You may be able to find a used 2007 Dodge Charger at your local Dodge dealership. However because it is an older car you may have more luck finding the car in a private sale.
Dodge Chargers can be found for sale at your local Dodge dealerships and listed for sale in your local newspapers. You can also go online and find them for sale on sites like Craigslist.
One can purchase a Dodge Charger 2008 from various websites like Amazon or eBay. One could also visit a local car dealer and ask if they have one for sale.
There is a website called Supaprice who will give you the best prices for car parts including those for a 1969 Dodge Charger. You might also try your local scrap dealer.
Check your local newspaper classifieds, local used car dealers, eBay, Craiglist, etc.
Locksmith? AAA? Perhaps dealer if you have V.I.N. Perhaps local Police