As far as I can tell the xorg.conf file is not installed by default, if this is wrong someone can correct me. I was able to find a bit of information about the xorg.conf file at the following link.
ftp://www.x.org/pub/X11R6.8.2/doc/xorg.conf.5.html
Here is another link that may be useful.
https://wiki.ubuntu.com/X/Config
ftp://www.x.org/pub/X11R6.8.2/doc/xorg.conf.5.html
Here is another link that may be useful.
https://wiki.ubuntu.com/X/Config
“I have not failed. I’ve just found 10,000 ways that won’t work.” - Thomas Edison