Our party uses Elk River Canoe Rental in Kelso, TN. Only one of us had their own open kayak. The rest of us used the rental facility's equipment which was actually pretty decent. All of us used kayaks of varying sizes. Call early to reserve the long yellow one.
The rental place has the life jackets and canoes/kayaks with reasonable rates (around 40 for the canoe and 20 for the kayak) and they'll pick you up at the designated bridge.
We spent a little over 4 hours on a Sunday afternoon. As the other author stated (report here), there are more than a few places where you have to watch that you don't run aground as it gets real shallow in areas, depending on water level, obviously.
There were 6 of us in our party. We all enjoyed ourselves plenty. One could take inner tubes and do the Elk as well.
The fee paid per person is for them to supply equipment (which includes lifejacket and canoe/kayak) and pickup/dropoff.
From Huntsville, AL take US 231/431 north to Fayetteville, right on Thornton-Taylor Parkway, then right on US Highway 64 East. Look for the Big Blue Canoe.