I did see the instructions. They weren't working. I read another comment about the web beta version not working. So I found an older version and now the stacking is working. Thank you.
I just signed up for the free version of Evernote to see if it will suit my needs. I created two notebooks and I am unable to drag one onto another to create a Stack. I've read the instructions and watched youtube videos with no luck. Is this option only available with paid Evernote subscriptions