compile error: X development libraries not found

[jay_gtk fastmail fm]

Hello,

I am trying to compile gtk+-2.8.9 on Debian Linux. I have a mix of
stable and testing packages installed.

I have successfully compiled glib, atk, pango, cairo, etc. When I try to
configure gtk+-2.8.9, I get this error:

checking for X... no
configure: error: X development libraries not found

When I try to install the libgtk2.0-dev Debian package, I get this
message:
---- BEGIN -----
# apt-get install libgtk2.0-dev
Reading Package Lists... Done
Building Dependency Tree... Done
The following extra packages will be installed:
  libatk1.0-dev libcairo2-dev libfs6 libpango1.0-dev libx11-6 libx11-dev
  libxaw8 libxcursor-dev libxext-dev libxfixes-dev
  libxfixes3 libxft-dev libxi-dev libxinerama-dev libxkbfile-dev
  libxkbui1 libxrandr-dev libxrender-dev libxxf86dga1
  libxxf86vm1 render-dev x-dev x11-common xbase-clients xserver-common
  xserver-xfree86 xserver-xorg xutils
Suggested packages:
  libcairo2-doc libgtk2.0-doc libpango1.0-doc configlet-frontends
  discover libglide2
Recommended packages:
  xresprobe laptop-detect
The following packages will be REMOVED:
  xfree86-common
The following NEW packages will be installed:
  libatk1.0-dev libcairo2-dev libfs6 libgtk2.0-dev libpango1.0-dev
  libx11-dev libxaw8 libxcursor-dev libxext-dev
  libxfixes-dev libxfixes3 libxft-dev libxi-dev libxinerama-dev
  libxkbfile-dev libxkbui1 libxrandr-dev libxrender-dev
  libxxf86dga1 libxxf86vm1 render-dev x-dev x11-common xserver-xorg
The following packages will be upgraded:
  libx11-6 xbase-clients xserver-common xserver-xfree86 xutils
5 upgraded, 24 newly installed, 1 to remove and 337 not upgraded.
1 not fully installed or removed.
Need to get 18.6MB of archives.
After unpacking 21.5MB of additional disk space will be used.
---- END -----

I decided to try to compile it from source, because messing with
installed xfree86 stuff could really mess the whole system up, right?

Is there a way to just compile the X development libraries that I need,
and point the GTK configure script to those libraries, without
reinstalling the whole xserver system ?

Which X source packages do I need to download and compile for GTK to
work? Is it possible to compile the X server libraries as shared /
dynamic libraries, and point the GTK configure script to those shared
libraries?

Thanks, and sorry if these questions seem a bit ... uninformed.

- Jay