You can download Ubuntu 6.10 (Edgy Eft) Server from the Ubuntu website. You should select your appropriate mirror. Once you have selected your mirror, you need to find the server install CD. There are 32- and 64-bit versions of this CD. The CD images are available in ISO image format and follow this naming convention, ubuntu-6.10-server-(i386|amd64).iso. Download the ISO image that suits you, and then burn it to a CD.
Burning a CD in Linux is quite easy; you can use the standard shell utility cdrecord. Or, since GNOME and KDE recognize ISO image formats, you should be able to right-click on the file and select "burn to cd" or something of that sort.
This was first published in May 2007