The official ftp site is:
  ftp://ftp.gimp.org/pub/gtk

Patches can be uploaded to:
  ftp://ftp.gimp.org/incoming

Anonymous CVS access for gtk+ (as well as 'gimp', 'gimp-data', and
'gnome') is available via
  CVSROOT=:pserver:anonymous@cvs.gnome.org:/home/cvs
with an empty password.

A mailing list is located at:
  gtk-list@redhat.com

To subscribe: mail -s subscribe gtk-list-request@redhat.com < /dev/null
(Send mail to gtk-list-request@redhat.com with the subject "subscribe")