This is going to sound completely insane but I can't find the viewport panel that was in 2010 in 2013. I have a panel for model space viewports but not paperspace. I am sure that it is a simple thing but...
Model Viewport Panel found under the VIEW tab in the Ribbon?
Or the Layout Viewports Panel found in the LAYOUT tab in the Ribbon?
Each panel is only active if you are in the correct model/paper space. In plain AutoCAD 2013 where you are posting if that's what you are using.
Look at the Layout tab and not the View tab.