Acrobat X doesn't add anything to the optional content group (OCG, aka "layer") manipulation features found in earlier versions, so to do anything major with layers you need to use third-party plugins such as ARTS PDF Aerialist Pro.
If you want to import one PDF page as an OCG on one page of another PDF, you can use the layers pane tools. Open the navigation tab on the left of the Acrobat interface and show the layers pane, then click the tools icon below the word "Layers" and select "Import as layer".
This will only bring in one page at a time, and OCG operations cannot be undone in Acrobat without a plugin, as Acrobat doesn't recognize the actions of the layers tools as a step on the undo list, nor can you delete a OCG or move content from one OCG to another (aside from flattening them).
To import the same page as an OCG on every page in a file (or a subset thereof) you should use the watermark or background tools (watermarks can add text too; but they both do the same as the tool on the layers pane, but don't list the new OCG in the stack). If you want to collate-merge two multi-page documents or merge pages of the same document into a stack, you'll need to use a plugin or automate the above steps using a script (though scripted solutions for this type of thing tend to result in a horrible mess).