Frank,
And just taking this "novice" route - could somebody please point me to a place where I can download a suitable "sid" cdroom image? I've check the www.debian.org now for at least 10 minutes and didn't find anything...
There are no distribution images for the unstable/"sid" branch, see http://www.debian.org/CD/faq/#unstable-images.
You have to get a testing/"lenny" installation (released daily and is checked for its soundness and installability), see http://www.debian.org/devel/debian-installer/. Select the appropriate "netinst" platform variant, then proceed with a raw installation. Then:
1. update your sources.list for the deb package manager (basically substituting "testing" occurrences for "unstable").
2. call "apt-get dist-upgrade"
3. your system will upgrade and will so track unstable
However, for production use, Dave Bauer's hint at the Ubuntu server installation (preferably the long-time support LTS version 8.04) is the way to go: you get the advantage of an assembled and checked Debian unstable, our packages, and security fixes through 2013.
//stefan
