Answer:
You can have a look there to see what's available

Answer:
Add the following lines to you /etc/apt/sources.list

deb http://people.debian.org/~bayle/debian stable/
deb-src http://people.debian.org/~bayle/debian stable/

or

deb http://christian.bayle.free.fr/debian stable/
deb-src http://christian.bayle.free.fr/debian stable/

(Christian's pages), or

deb http://people.debian.org/~lolando/debian unstable/
deb-src http://people.debian.org/~lolando/debian unstable/

or

deb http://roland.mas.free.fr/debian unstable/
deb-src http://roland.mas.free.fr/debian unstable/

(Roland's pages). Depending on our real life activity, one may be more up-to-date than the other.
Then run:

apt-get update

You have now several possibilities:

• You never installed any sourceforge or gforge package, just:

  apt-get install gforge
  

  and answer carefully to all the questions, it is preferable to let the install touch your config files, though it's not the default because of debian policy.
• You want old sourceforge (more tested than gforge, with themes and foundries, almost the classical 2.6.1 coming from the last known cvs snapshot from VA.

  apt-get install sourceforge
  

• You want new gforge, but you have already sourceforge installed
  

  apt-get install gforge-sourceforge-transition
  

  will dump your db and move your files, then

  apt-get install gforge
  

  will uninstall sourceforge and install gforge with the dumped data

Answer:

• From debian distro
  

  apt-get source gforge
  

• From CVS
  

  cvs -d:pserver:anoncvs@subversions.gnu.org:/cvsroot/gforge login
  

  And just return for the password

  cvs -z3 -d:pserver:anoncvs@subversions.gnu.org:/cvsroot/gforge co -d gforge-3.0 gforge
  

Answer:
http://savannah.nongnu.org/projects/gforge/

Answer:
http://fusionforge.org/

Answer:
go into gforge-3.0 dir and run

debuild

The debuild tool is in the devscripts Debian package. If you run this command on Debian Woody (stable), you may have to upgrade some needed tools (debconf, debhelper, ...). To do that, add the lines for Debian testing in your apt sources file and then try something like:

apt-get -t <needed version> install debhelper

When the packages are built, do the following:

mkdir /directory_of_your_choice/debian
cd /directory_of_your_choice
dpkg-scanpackages debian /dev/null | gzip > debian/Packages.gz
echo "deb file:/directory_of_your_choice debian/" >> /etc/apt/sources.list
apt-get update
apt-get install gforge

Answer:
For more info you can join us on IRC at irc.openprojects.net on #gforge (GForge package) or #debian-devel-fr (French)
Mailing lists are there: http://savannah.nongnu.org/mail/?group=gforge