The “X Strike Force” takes care of packaging X.Org for Debian.
These documents are shipped in the xserver-xorg metapackage (under /usr/share/doc/xorg), starting with wheezy. They are also available online at x.debian.net, which is an alias for the longer-to-type pkg-xorg.alioth.debian.org.
/usr/share/doc/xorg
wheezy
General FAQ
How to report bugs
How to triage bugs
How to use GDB
How to configure input
How to configure outputs
How to build mesa
Using git for X repositories
Dependencies between server and drivers
Backports of the whole X stack for squeeze
Upstream contacts
Upstream features
Sources for these documents are available on git.debian.org.
Patches, suggestions, flames, etc. are welcome, using the debian-x mailing list.