The 4players.de is the same thing, it's just a little more expensive because it comes with a CD etc.
You can just pay for it through the homepage and not have any problems and just download it there, no need for a CD.
i would not recommend doing that, there are hardly any S1 servers (although scawen mentioned he wants to change the system soon)
you actually don't really need a cd, just go for the 36 euro version with all the cars and tracks plus 32 racers grid
in times with dsl it shouldn't be a big thing to download a 150mb executable
there is a nice online wiki (also in german) so the handbook isn't needed either