This is a sketch of the floor plan of the fictional West Wing during the first season. Susannah sketched it while she was on the set so this diagram is not to scale by any definition of the word. The area around the press room is kind of a guess because the press room set isn't actually connected to the rest of the set so it's kind of hard to figure out how they relate.

Over the hiatus between seasons one and two they expanded and changed the set. Ozwitch spent a lot of time in front of the TV trying to puzzle out the changes and update Susanah's floorplan and was generous enough to post her updated version.

As you can see, C.J.'s office was next to Josh's in season one, but they moved her over next to the press area in season two, which apparently allowed Josh to install a mini-bar. The little room behind the seal in the lobby is where the boys were sitting during "Shibboleth" when the turkeys were delivered. The four dots in Josh's bullpen are the atomic clocks. Ainsley's office is downstairs, as is the mess and presumably the Situation Room, although it's not entirely clear.

The actual West Wing of the White House differs significantly from the one on the show. In addition to being smaller, with fewer windows and fewer people walking quickly through the halls, there is no Mural Room (in the real West Wing that's where the Cabinet Room is). For an excellent overview of how the real West Wing is laid out, visit http://www.fas.org/nuke/guide/usa/c3i/peoc.htm.