How big is the good year blimp?

Pretty big. The wikipedia article linked below for the Skyship 600, the most common advertising blimp, gives a length of 66 meters / 216 ft and height of 22 meters /72 ft 2 in.

But this is nothing compared to whats possible. The Graf Zeppelin measured 244 m (803 ft 10 in).. modern blimps are approximately the size of one of her fins.