That's an excellent new book by Roger Moorhouse. I found good material on virtually every page:
Heinz Knobloch was dispatched by his mother to a department store by the Hallesches Tor to buy something — anything — exempt from the rationing. He managed to return with two tins of sardines. He was lucky to have escaped with his booty intact: the new legislation against hoarding meant that some of the more punctilious shopkeepers were already insisting on opening all tins immediately upon purchase.
I also learned that many Berliners starting suspecting the Holocaust because of the rather efficient German postal system. When letters would be sent to "ghetto inhabitants" on the Eastern front, often they would be returned with notice that the intended recipient had passed away.