ANY COMMENTS AND/OR ADVICE IS APPECIATED

I drive a honda accord coupe 2000, it has a stock double din radio/cd player. And i'm sure its quite customizable, considering its a honda. I want to put in an in-dash lcd monitor, I found a nice panasonic one (Panasonic CQ-VA707W 7" Diagonal Color LCD Monitor) for roughly 700 bucks. The reason I'm going with this one is that it comes with a built-in 4-Channel High Power Amplifier , and this is what I think connects to the car speakers, correct me if I'm wrong. Then, I'll be buying an ezgo mini computer which I found on directron.com and i'll get one gigbyte, 256 ram, and 20 gigs harddrive. This ill place in my glove compartment. Then, ill need a touch pad, usb. Also, gps earthmate would be nice, along with a usb wireless network adapter. I really am unsure about the whole power supply and when the system will turn on and off, will it automatically happen when I start and turn off the car?