On Debian GNU/Linux, gtkmm 2.0 is available in unstable/sid. You can install gtkmm by typing this on the command-line:
apt-get install libgtkmm2.0-dev
If you use stable/woody however, you'll have to compile gtkmm2 yourself.
Red Hat Linux
TODO, including location of examples. You'll need to copy the examples subdirectory
to your home directory, or some other place where you have write access,