@ Larry K, did you check out Craig's Lost Chicago. A lot of pictures from yesteryear of lost businesses. Just click on one of the 'lost entries" at the top.
http://www.craigslostchicago.com/
Also you might want to check out Chicago Pass. Another website with a lot of good pictures as well.
http://chicagopast.com/
Another website is PicturingUs. I just found this one. This site is broken down by neighboods in the city.