I am trying to find exactly where the credit expansion for the WWI war spending distorted, are there any good sources on what specific assets and markets it affected?
Take a look at Benjamin Anderson’s book, Economics and the Public Welfare:
http://library.mises.org/books/Benjamin%20Anderson/Economics%20and%20the%20Public%20Welfare.pdf
And Gene Smiley’s article, The U.S. Economy in the 1920s:
http://eh.net/encyclopedia/the-u-s-economy-in-the-1920s/
Also take a look at the sources cited by Tom Woods in his article on the 1920-21 downturn:
http://mises.org/daily/3788