Hi Carl,
This book should be useful to you:
- "Der Einsatz der deutschen Luftwaffe uber dem Atlantik und der Nordsee 1939-1945" by Neitzel, published by Bernard & Graefe, 1995, ISBN: 3763759387
Out of print but not hard to find. If you need it, I can provide more detail about the contents when I get home tonight.
Hope that helps,
Leon Venter