I agree with others:
Skip Granite City in the Twin Cities:
Go instead to Summit in St. Paul, (good beer, (3x 10 oz samples too!), free tour, and fun medium sized craft brewery).
Most importantly, GO TO SURLY in Minneapolis, (Brooklyn Center to be exact). The owner of the company is your tourguide, and he's full of stories. The beer is to die for. You get 5 tokens at the start of the tour, each good for a 4 ounce pour. I'm pretty sure that's a legal thing, as they don't really care how much beer you drink. They love their beer, and love their brewery, and Omar loves to show you around and talk about his brewery.
Edit, Surly Tours are EXTREMELY tough to get into. They do one tour, every Friday night, (unless they don't feel like it), and reservations open 3-4 weeks before the tour date, (usually 3 weeks, usually on a thursday night). You can reserve as many slots as you want, but the reservations fill up usually within about 3 hours.
www.surlybrewing.com . Good luck!