Hopefully the unwanted guest was only stopping in for a night. Do you have any dogs on your place? Our dog was usually the one that notified us of the stripped kitty in the barn- they would get sprayed.
Try a live trap works because if they can't lift their tail they won't spray. I wouldn't attempt to grab it's tail, they are very vicious...my dog got into it with a skunk once and the skunk put some pretty deep holes in my pup.