www.botanicalinterests.com - I highly recommend this company. They have great quality seeds and they have good prices. They also have some hard to find seeds and many heirloom varieties.
www.burpee.com - This is a good company and they have been around a long time. They have a lot to choose from but are kind of expensive if you order online. This companies seeds are sold in many retail stores for much cheaper.
before last I bought 2 of them on E-bay and they were shipped to me from N. Carolina. The first winter I kept them inside on an unheated covered porch. Sadly the next summer was really hot and dry and one of them died but the other one seemed to be doing well. So I left it outside put a tomato cage around it, stuffed it with leaves and straw, wrapped it in several layers of bubble wrap than covered the top with a trash bag to keep it try, because rotting I hear is a problem. When I checked it in January it still was green so hopefully it will pull through the winter. Here are some before pictures taken during the summer and pictures of it all protected outside in the snow.