It's really getting a bit late now, unless the plant is a really good size and needs to go in.

If you've got one, and it's a small plant, pot it on, and I think I'd keep it or larger ones as well in a sheltered corner until spring. You might need to insulate the pot with bubblewrap in the case of severe weather to avoid the rootball from freezing.

If you're thinking about buying one, then I'd wait until next spring.