You will definitely want to tap into the map light circuit.
This way it will come on when u push unlock, door open, turn your car off, etc.
I actually did something similar with 4 12" white ccfl tubes.
You can get to these wires right at the BCM (in front of driver side door)
Heres a picture with the info u need (this is the connector furthest right):
Pin 1: Red/Black (+12v)
Pin 8: Purple/Red (-)
Its very nice to have them go on/off automatically. Good luck!
Here is the final result of my install:
