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The City of Regina website has a photo/biography of the month where they either post a picture from the past with a bit of info about the photo and the people/places/events in the photo or they post biographies of various citizens. Do many other city websites have something like this available? It's interesting to read some of the stories. Lots of old pictures, too.
The Glenbow museum has a large digital collections database, where it is possible to find photos, CPR Land Sales, maps, yearbooks, etc. I use it almost exclusively when I am finding old photos of Calgary.
There are other quirky archives all over the web. Sometimes pictures from your city are found in archives of other places, for example there are a few Victoria pictures in the Washington and Vancouver archives.
Go to Indiana's Cushman archive and enter "Winnipeg" and you'll see three great colour aerial pictures from 1961 of the suburbs.