[PLUG] How to configure repositories in Debian

[John Jason Jordan]

I have a catch-22. I can't install anything on my new Debian
installation because I installed it from the DVDs. I can uncheck the
DVDs in Synaptic, but I can't figure out how to add repositories. At
the moment Synaptic lists 1343 packages, almost all of which are
installed. In Ubuntu there is a list of additional repositories and you
just check them to use them, but I can't find the list in Debian.

I can't ask anyone in Debian-land because apparently all support is by
e-mail. And I can't get e-mail working until I can get Sylpheed
installed because Evolution is incomprehensible.

Enough frustration for one day. Maybe in the morning things will make
more sense.