Finding debian etch iso’s was little crucial when things doesn’t work well during upgrades. Especially when the drives go wrong and you have to continue running the good old distribution, better keep a copy of the ISO’s.
Here I found those ISO’s to get going.
https://ftp.ch.debian.org/debian-cd/4.0_r7/i386/iso-cd/
https://iso.linuxquestions.org/debian/debian-gnulinux-4.0r1-etch/