Well, I went to just about all of the places mentioned above. Nicollet Mall certainly was a great area, I'm going to have to go back before I leave. I also found what I would consider to be a 'local gem'. http://www.hammer-made.com/
The store "Hammer-Made", if you can fit into their sizes, has amazingly soft Egyptian cotton (in the 'true' sense of the word, not the "oh just a generic cotton from Egypt" way) shirts. They also offer a MTM option. Unfortunately they didn't have my size, but the owner was extremely nice and I even met their designer there. I'd definitely recommend them as a local shop -- I liked their shirts more than some of the RLBL shirts I've encountered. One disclosure: since I didn't find my size, I can't attest to their longevity. Edit: and right next door there was a store called "Twill by Scott Dayton" that sold some staples (e.g. Talbott ties). I wasn't sure which line the products were, though, so I was a bit wary to shell out that much money.