Gnus is distributed as a compressed tar file of Emacs Lisp files. The primary Gnus pickup point is in Norway, but this is mirrored in:
Older versions of Gnus can be found in:
An archive of patches is also available.
If you are running Gnus under XEmacs, you should also pick up the package of icons.
The Gnus Network User Services site can be found two places:
The proper incantation for checking out the Gnus sources the first time is this:
$ cvs -d :pserver:gnus@cvs.gnus.org:/usr/local/cvsroot login
CVS password: gnus
$ cvs -d :pserver:gnus@cvs.gnus.org:/usr/local/cvsroot checkout gnus
(You type the bold parts.)
You can then rename the resulting gnus directory to whatever you want -- like, for instance, pgnus.
After doing this, to get a fresh Gnus, all you have to do is say:
$ cd pgnus
$ cvs update
Please note that what you're getting is probably not even a
bleeding-edge Gnus, but a severly hemorrhaging one.
If you just want to browse the repository, you can use cvsweb.
If you think you should have write access to the repository, write to Lars and tell him so.