Hi Klaus,
The best resource on Transportflieger is this book:
- "Die deutschen Transportflieger im Zweiten Weltkrieg" by Fritz Morzik and Gerhard Hümmelchen, Bernard & Graefe Verlag, 1966, 320 pages
The book covers organization and aircraft (20%) and transport operations in all theaters (80%.) It lists forty Transportflieger Ritterkreuzträger, the first being awarded on May 11 1940 and the last on Feb 28 1945.
Hope that helps,
Leon Venter