If you're currently editing a document, tap "my documents" to go to the list of all documents and then "new document" - it's Apple, try not to over think
Ah, I just has a thought, I bet the menu bar at the top of the screen was hidden - that's not the default, another user would have had to do that before you played with the iPad. With an empty screen, I can certainly understand the confusion. If you had hidden the menu your self, you would have know how to get it back, and all would have become clear.