Microsoft has recently launched an "online service page" for Xbox360 owners in Germany, Austria and Switzerland. This kind of service has been available for owners in United Kingdom and some other countries, but not for German language owners.
Owners of the Xbox 360 will be able to register and confirm their warranty status. They will also be able to request the repair of their Xbox 360 and track its repair status via this site.
You can check out the site here.