Since I found a different method to achieve my goal, and since no answer was posted to my previous question, I've changed the question to match the answer I found.
Is there a way to turn off my laptop's monitor and turn on the external monitor(and vice-versa) entirely from the command line?
xorg.confinto the root (/root/yorg.conf.new) directory, if you boot into recovery mode and executeX --configure(or similar). – Bobby Jun 21 '10 at 14:24