http://www.lib.uchicago.edu/e/su/maps/chisoc/G4104-C6-2W9Q4-1930z-U5.html
There is also a set of map images copyrighted in the 1950s but were apparently made in 1926. You can access them through this website:
http://sanborn.umi.com.proxy.uchicago.edu/
Click on Browse Maps, then select the state (Illinois), the city (Chicago), and the date (1905-1951). At the top under "Select a volume" select vol. 16 1926-Oct 1950, the plate numbers we would probably use are 27-32 and 40-46. No blueprints though, but from the looks of it they were mainly retail shops, a barber shop, and even a gallery.
If anyone wants to (and would like to do me a big favor since I'm finishing my BA that's due tomorrow) you can get a better image through microfilms. I have the microfilm call numbers, so if anyone is up for the task, message me and I can give them to you. Sorry I couldn't find any blueprints (or any maps later than 1930).