I've heard of some of the spots to see native slippers but most are kept secret to protect them...
quite a few are in spots where many people know about them and get visited quite a bit. there are a good many in the cortland general area that are on cornell plantations property or in some of the many bird preserves. the one just north of me is on private property but allows people to visit the spot as long as they are respectful and no picking etc. if you know someone who knows someone and all the word gets spread around quite a bit