DKU

If it's a DKU championship you want to sign up to, then you can fill out a formula by following this link.
At some championships you have to be a member of DKU to participate (e.g. the Danish Championship).
DKU championships are always played in Denmark.

Germany

If it's German Open you want to sign up to, then contact Hotel prinz-Luitpold-Bad.

This championship is always played at 2. Saturday in Juli at Hotel Prinz-Luitpold-Bad in Algäer Alpen, Germany.
You can also check out this German site: www.krolf.de