Need advice for start kill

Hi all...Just had my second car stolen in 10 years. I had an alarm but I guess they ripped out the siren and just popped out the ignition and flipped the valet switch to valet mode and bye bye car. I was wondering what can I do to disable them from starting the car. Something that is independent of an alarm. I saw some relay set up for starter disable using a switch or something in the car but I just don't know what to do so the darn cars won't get stolen anymore. I just got a new 04 accord and don't want this to be another statistic. Help and thanks.

fuel cut off is the best.

The immolizer that comes on your Accord is going to be better than any relay you could install. Your car can't be hotwired, nor could a new ignition be plugged in and the car started with a key. The cars computer won't let the car start without seeing a valid programmed key.