For all the best German music from the period, go here:
http://u-boot.realsimulation.com/
Click on SH3 Grammaphone Downloads, and get the files German Hits 1910-1929 all the way through German Hits 1945. They need to be unzipped, and they may need to be converted to .wav or .ogg format, but with those you will have more than one hundred songs to listen to.