The setup on the VZW X will only allow you to add apps/widgets to the right. When you grab one from the app drawer or widget screen and it defaults you to the "main" home page, just keep holding it and move it to the right end of your screen to force a page scroll. It will only scroll over as far as your existing screen +1 one screen. So you have to "build" the screens one at a time that way.
Personally, I preferred having home screens to the left and right of the main screen. I was able to organize things much more efficiently that way.