Highly recommended. There were also German tapes of Allied prisoners, but those have not yet been found!
Sönke Neitzel, Professor of International History, London School of Economics, discusses his investigations into the mind-set of the German fighting man during World War II. Soldaten: On Fighting, Killing, and Dying, written with social psychologist Harald Welzer, is based on declassified transcripts of covert recordings taken within the confines of the holding cells, bedrooms, and camps that housed the German POWs, providing a view of the mentality of the soldiers in the Wehrmacht, the Luftwaffe, the German navy.
See also
What it was like, specifically:
Tapping Hitler's Generals: Transcripts of Secret Conversations, 1942-1945. Farm Hall for captured German generals. Who knew what, when? More here. Those tricky Englanders!
For more on Farm Hall, where German nuclear scientists were held and secretly taped, see
The Heisenberg uncertainty.
