Here’s another layout of the West Wing, and here’s one that even shows were Josh and CJ’s offices are. 
This site has a large floor plan of the second floor, extrapilated from the other floors and photographs. It’s also got links to Library of Congress detailed floor plans of the Ground and First Floors.
This site’s got a layout of the third floor based on blueprints from the last time it was renovated, during the Truman administration.
Eric