Car Computer?, Ideas? Options

[cnelson]

I would like to install a car computer. I need to know about how much it would cost me. I just want to take an old laptop mount it somewhere power it up to a touch screen monitor then somehow rig it so when the car comes on so does the laptop and when the car shuts off so does the laptop. I also want GPS. I know its a big under taking but i have high hopes on how sweet it would look. I posted in pittfire's theard but he hasn't been around in a couple days so i made my own topic. -cnelson.

[cnelson]

Hmm, i know i've looked on there before but heres what i really want to do and i know with a bit of modding it can be done for under 500USD. I just need the help of some people to point me in the right direction. ok heres the outline for the project;

A: Buy a touch screen in dash 7in monitor. 250USD.
B: Get a laptop off ebay cheap, then use an external harddrive to get more out of it. 200USD.
C: Rig the laptop and screen to turn on with the car and turn off with the car. Thats what i run into troblue, i don't know how i would do that. I would then just mount the laptop under the seat or somewhere run a USB hub in an easy to reach place.
D: Like i said somehow i have to rig the laptop to turn on with when the car starts and off when i turn the car off. I also need to install a converter from 12v to 19v which is what laptops take. Then i need to run the cables to the touch screen in the dash. Now will i also still be able to use the radio somehow?
E: And i need to know how to hook up the speakers for all this. Probably won't be hard but i still don't know how to do it.
F: In a nut shell that is what i have to do. Also i need to hook up a GPS system somehow and a backup camera. I know its a big under taking but i really want to do it.

Also i read though the "How-To" on mp3car.com that the guy made on the celica but he builds his computer from scracth thus there is a lot more information that i don't need in that making it harder to understand. I know my way will work, i just need some of those question answered. Thanks. -cnelson.