I grow lots of Gloriosas in my garden too, and they die back in winter even in central Florida but come back every spring and bloom off and on all summer.
You'll have trouble finding any tubers to start at this time of year. They're usually sold out. So if you can wait until next spring, jmorth's offer is a great start.
By the way, if you could fill in your personal profile with your location, we'll have a better idea on how to answer questions for you in future.