Car alarms, gps tracking, car stereos, etc

[guids]

I am getting my new escalade next week, finally. It is pretty plain jane on the interior, no onstar, no nav, just a cd/tape player, with rear control in the console too. Im going to get some stuff for it.
I need:

1. Car alarm w/ GPS tracking (in case it gets stolen), preferably one with remote start

2. It has a factory bose system, should I get the speakers replaced? I want at least one sub, and a new head unit.

3. DVD player and screen for the front of the vehicle??? is this illegal?

4. nav?

[Redd]

Guids,

Regarding 3 and 4: if you're willing to do a fair amount of work, you can do some pretty amazing things with the info in the www.mp3car.com forums. They're hobbyists who specialize in installing standalone PCs in their cars.

[guids]

you know what? You are a son of a bitch. now this is going to be a lot more involved than I had planned. Im a huge dork when it comes to this stuff, and will have to do it. seriously, site looks awesome, ill probably end up doing something with it. thanks.