Coastal Seafoods carries a variety of fresh fish, much of it flown in daily. This quality does not come cheap, however, so be prepared to pay as much for a pound or two of fish as you would for a meal at a mid-range restaurant. Also, their in stock quantities are often small-so make sure to call ahead if you need a particular fish for a special meal.
Their fresh tuna is the best in the Twin Cities. However, I've found better and cheaper unagi next door at United Noodle.
They also carry a premium grade of Kobe Beef, which should be fun to try.
Be sure to check out Coastal Seafoods website for their daily and weekend specials.