Thanks for your thoughts jimbob.
I already asked Don about writing for ethicalhacker.net but it seems that there are already enough writers, so.

I will check the SANS Reading Room, thank you very much for the hint.
In terms of the CV.. how would one write published articles in e.g. SANS Reading Room? Same as with published ones?
So far I wrote something like:
"Title of the article", Magazinname, Date
I think too that it is better for starting to contribute one, two chapters to a book to get more experience at all. I guess I will give Syngress another try and back it up with a few examples of my writing (although I did this already).
Any other recommendations and thoughts are highly appreciated, thanks.