Dear Mark,
I am not an expert in this area but have you tried with any of the following sites:
Norway during WW2 Forum
http://www.f16.parsimony.net/forum28300/
Biplane Fighter Aces from the Second World War
http://surfcity.kund.dalnet.se/ (a lot of information about 263 Squadron)
Flyvrak,
World War II Aircraft wrecksites in Norway http://ktsorens.tihlde.org/flyvrak/
Nordic aviation during WWII
http://www.rafandluftwaffe.info/luftwaffe1.html (includes information about German losses in Norway)
I have not read it but I assume the book ´Fledgling Eagles:
Complete Account of Air Operations During the "Phoney War" and Norwegian Campaign, 1940´by Christopher Shores has a loot of information.
Regards
Peter