Hi Pa,
if it's repairwork you need doing, alex guitars does most of the pros I know (including me). www.alexguitars.de (I've just checked their link and keep getting re-routed to some other bogus site. Anyway their telephone number is 030 247 23122
Ken Skversky (an American guy) is also good and reliable. http://www.guitarserviceberlin.de/
Or you could try guitardoc http://www.guitardoc.de/
I haven't had any bespoke stuff built here, but this guy has a very good reputation http://www.nickpageguitars.com/
Hope this helps.
Cheers,
Paul