http://www.phidgets.com/
I use the 8/8/8 interface board with LCD, a colleague of mine is using the 8/8/8 board with an USB hub. Since my car's fuel level sensor is resistance-based, I could just connect its output to phidgets analog input. Some newer cars use capacitive sensors - if this is your case, you might need to build a little adapter to convert the capacity to voltage (in range between 0 and 5V).