Audio installation in Southern MD, SW PA

I'm looking for someone in the Southern MD or SW PA area who can install audio components I plan to purchase for a 2007 Prius:

• XM Direct satellite radio module to work with the car's satellite-ready radio.

• VAIS 2L2i and SL2X components to integrate an iPod and the satellite radio as part of the navigation system.

• Shark fin antenna.

Any suggestions would really be appreciated.

P.S. I am an electronics imbecile.