Well, I'm member of the two Tatra-related forums on Yahoo! which are both in English:
Both are very lively, but Yahoo!-groups do not have the division in subjects that this forum does, which makes specific subjects very difficult to trace.
With a little luck, many of the users from these forums will show up here, once the word gets around. I just hope that the users of the Slovak forum will have some fun with this too and post some threads.
We are currently a mere 8 Tatra-owners in Denmark and even though most of us are experienced do-it-yourself mechanics, we are bound to run into some kind of trouble every once in a while. And then it would be invaluable to have access to a forum with so many other owners (who must have gone through the same problems?). I know I certainly have some issues with my car that I would like to discuss with others!