Etch is obsoleted distribution. Unless you have specific reason, please
use current release: lenny.
http://www.debian.org/distrib/
I have no idea what is hapening on your system. Are you connected to
network and tried to download packages? URL for archive has changed so
old install disks are not expected to work without special tweak by the
user. New URL for APT lines are http://archive.debian.org/
If you learn basics of APT system, it is not so difficult.
http://www.debian.org/releases/stable/installmanual
http://www.debian.org/doc/manuals/debian-reference/ch02.en.html
Osamu