Make-live is a brilliant Debian application for creating an up-to-date Debian live CD and Ben Hay explains us in his usual way how to use it.
It actually is quite seriousely, allthough he likes zombies, but:
Anyway, once you've installed make-live (apt-get install live-package) you can just type “make-live” to automagically build an iso of your very own Debian live CD. It really is as simple as that. Well, it is that simple if you don't mind downloading all of the required packages each time you wish to build a CD. This can be hundreds of MB at a time.