I saw some absolutely fabulous b&w Halloween fabric at Hobby Lobby but it wasn't a panel. It sure was gorgeous though! I didn't buy any as it was not on sale and I know they'll put it on sale soon. I wish I took a picture of it now since HL doesn't sell fabric online :(
I will keep an eye out for it.
Have you searched the board for Halloween? Maybe you'll see the post you were looking for?