The event will be held at Kloster Graefenthal which is located at Maasstrasse 48-50 47574 Goch, Germany.

Tickets for David Tennant's photo ops (solo) cost €164.39 and for his autograph sessions the price is €139.28.
There is also an option to have a photo op with David and Peter Davison for €195.78.
A ticket also needs to be purchased for entry to the fan convention.

Proud Nerd fan convention aims to connect the two fandoms Doctor Who and Good Omens.

Proud Nerd fan convention website

Link to posts related to David Tennant at Proud Nerd fan convention on Blogger.com (usually with more details).