I lived in Mpls. the first 18 years of life, left for college etc. The wife and I moved back last summer, so I have some knowledge of the area.
Summit Ave. is old money. Huge houses, home of the Gov's mansion and Garrison Keillor.
Grand Avenue is nice neighborhood. Hip, diverse, old. They fought off "Noodles and Co" restaurant.
Frogtown (Payne-Phalen neighborhood) is one of the tougher parts of St. Paul. That's an area for a good crime story, imho.
There's a St. Paulite named Tom (T.D.) Mischke. A local radio talk show host, musician, writer, humorist and one helluva' story-teller. Here's his bio:
http://en.wikipedia.org/wiki/Tom_Mischke A true St. Paul-phile and knows his history.
He's a bit of a recluse, but if you could get a hold him, I think he'd be able to help you out. Try emailing him from his radio-show website.
Another good link:
http://www.mischkemadness.com/mischkelinks.html
Shoreview and North Oaks aren't much, suburban-like. The later being a wealthy neighborhood. The real characters are in the downtown neighborhoods.