editing top menu nav

ok so heres the address http://www.ipokerbiz.com/wordpress/ ….at the top where it says home and about, I want to add more tabs like the about one, I can add and remove the home tab but I cant find the about in the header code. It should be just beneath it but I end up taking out the search with it and cant find anything that says “about”. could someone plz help its keeping me from major progress