Why can I not select vertices located behind others? When I use B only the front vertex is selected and not the one behind as well. I have tried turning on and off the Limit Selection to Visible and there is no change at all. I have tried all the tricks people have suggested and its still not working.

I appreciate any help.
Instead of moving the vertices or just changing the view you can change to Wireframe view with the Z button (by default). Then you can select all vertices hidden by faces, edges or other vertices. I use the Z key a lot since sometimes two vertices are in the exact same position.