500 Hill Ave. E is the correct location. The snafu is that the road is actually named E Hill Ave SE :blink: If you follow your GPS to the 500 address it will take you to the one way entrance to the hotel. The other side of the entrance road is the Women's Basketball Hall of Fame, you absolutely can't miss the two huge basketballs that are part of the building. The Marriott is an odd taper shape and with the big balls, err, big basketballs you have the best landmarks you can ever ask for.
Edit: I've got pictures of it someplace. So far all I can find is our pictures of the Sunsphere from the '82 Worlds Fair. The 'sphere is another place to visit in Knoxville. Ride up to the observation deck and have a look around, it is now free AFAIK.