If the glider is type certified in Germany (which it is most probably
because otherwise it wouldn't be allowed to fly in the US), the former owner
has to apply for de-registration in Germany (sending in the form, the
original certificate of airworthiness and the original certificate of
immatriculation), and the LBA then issues a certificate of de-registration
to the former owner. That takes 3-4 weeks, plus the snail mail from the US
to D and back.
There is no LBA webseite listing immatriculations vs owners.

Bert
wrote in message
oups.com...

I am buying a used glider and it's in the US. Is
there a German website that would show aircraft registry with names
next to registration numbers like we have here in the US?