Maxine, I got the start of mine as a gift from my kids for Mother's Day year before last. I think it came from Logee's. I've never seen it in nurseries here.
There are other passion vines that are just as pretty and not quite as cold-tender, so you might want to consider them before you go on a 'quest' for this particular one. Even on the coast of Alabama you're most likely a little bit colder in winter than we are.
This is Lady Margaret, dark burgundy flowers with white centers, no fruit though.
And this one is Purple Possum, my faithful fruit bearer - purple fruit like you pay $3 at the grocery store for. Flowers are really pretty, too.
And Passiflora Coccinea, this one doesn't fruit either, but it's the most common one you'll find at nurseries. Vigorous and flowers almost year 'round.