Where and How to tape 12V power for anti-theft security lock

[wwbear]

I am going to install an additonal automatic anti-theft security system to my Versa. But the system would need a 12V supply.

Where and how could I tape the power from (power for audio, fuse box,....)?

I am new to this stuff but I would want to try DIY instead of paid and knowing nothing to my car. It is very grateful if any would could post pic also. Thanks a lot.

[the converted]

Go straight to the ignition harness and tap in there. However alarms are only as good as the installer, so this is not something I would recommend for someone to take on as an introduction to car electronics.