I've installed X.org 6.8.1(and 6.8.0 for that matter) on my Debian box, wasn't very difficult.
Extract sources, copy xc/config/cf/xorgsite.def to host.def, then add whatever options you want.
Me, I just added the following:
#define ProjectRoot /PATH - This will put the installation in a directory of your choice
#define NothingOutsideProjectRoot YES - And everything goes in there
#define HasFreetype2 YES - If you have FreeType installed
#define HasFontconfig YES - Same as above but FontConfig
Then just "make World && make install"
Me, I installed it in /opt/X.org-6.8.1 and then symlinked /usr/X11R6 to that directory.
There are probably lots of other nifty options you can put in the host.def file, I'm just lazy so I never looked any others up
