For gear: the bookstore on campus is good but will be PACKED. You might stop by McMillan's for better prices than Hounddogs, or go to both -- both have stores off Cedar Bluff.
Eats: I personally think Calhoun's food is only so-so. Cool atmosphere, but there's better grub, for sure. Personal favorites: Riverside Grill (excellent food, and overlooking the water like Calhoun's), for a "nice meal" you can't go wrong with Regas or the Orangery (but bring your wallet), Sushi -- Nama, Brew/bar food -- Downtown Grill and Brewery on Gay Street, and for beer selection, you can't beat Preservation Pub in Market Square. Of course, if you just want to see and be seen, the old standby O'Charley's will be the place to squeeze into.