3D option is not on my menu bar , and none of the tool seeting show 3D options either. All Screen shots I have seen of Photoshop CS6 have this and I don't. WHY?
I assume that you have Photoshop CS6 Extended (not Standard) installed since there is no 3D menu in the Standard version.
3D is not supported in Photoshop Extended CS6 on Windows XP so if you're running XP you won't see a 3D menu.