Rum River Tubing. The Country Camping Tent and RV Park offers kayaking, canoeing and tubing as well as a place to stay. In Isanti, MN, about a hour north of the Twin Cities.
Cannon River Tubing. Welch Mill Canoe and Tubing do exactly what their name suggests. In Welch, MN, a little under an hour south of the Twin Cities.
Apple River Tubing River's Edge Apple River Campground has tubing, camping and waterslides. In Somerset, WI, about an hour east of the Twin Cities.
Also in Somerset on the Apple River, Float Rite Park has camping, cabins and tubing.
Or you can tube the Apple River with Apple River Hideaway, also in Somerset.