http://www.answers.com/topic/gun-laws-in-the-united-states
I looked up Tennessee on this sight and find no restrictions. Perhaps a telephone call to your local post office head quarters, or police departmentmight give you some better information... Also call you local UPS and ask them if it is legal since most of the on line dealers will ship through them anyway.
While it is legal to ship to Wisconsin, I have ran into people working in Post Offices that do not know the difference between a firearm and a antique firearm. They simply refuse to ship. Even when you tell them the statute where it is allowed.