Sunn - Viewport Art - [This is the artwork horizontally at the bottom of the screenshot behind the actionbars.]
Bartender4 - [The actionbar addon.]
ButtonFacade - [Actionbar skin is set to circles it looks like.]
Sexymap - [The blue circle around the minimap.]
Basically, Sunn - Viewport Art is a design that goes on your screen. Unfortunately, it makes your screen seem a lot smaller because it crams the screen into a wider view when you extend the artwork vertically which is why most prefer not to use it.
By the way, on the page you linked, if you scroll down, it says "Addons in this pack:"