Where can i get affordable upgrades: lcd headsets, dvd, etc... for my wifes RX300, in miami florida?

[mmx]

Instead of trading her car for a new car, we are going to....Pimp her car.

I want to add dual LCD headsets, dvd, etc...

However i can buy the stuff cheap online, but installation is a problem. So where in Florida, especially miami can i go to buy and have it installed?