Hi Dean,
The only people I know that are currently using marquetry techniques for cues (on a regular basis) is Longoni. There used to be a guy on this chatline named Solarte, though, and I believe he was altering or re-making old marquetry cues. That might not have been the case, but he had some very reasonable prices and the cues were just a little off from your typical pieces, but very subtly, like the borders and some of the inlays could be missing or look like they might have been from another marquetry cue, but you didn't catch this unless you really looked hard. Here is a thread from him. Scroll down about two thirds of the way and you'll see one of his cues. You might also check some of his other threads, as I know he had a few for sale:
http://forums.azbilliards.com/showthread.php?t=118059&highlight=marquetry
I've only owned one marquetry cue (attached pic). When I got it, I had seen several in books, but never one in person. A friend had said he wanted one and would make me a great deal, if I could find him one. I had a great trade arranged and when the cue arrived, I just about died. It was really short and everything from the butt up turned into a 3/8" dowel without a tip. Not your typical cue! Fortunately, it was exactly what my buddy wanted, but it was a shocker to think these actually played pool at one time. I think mine was like a shuffleboard cue that you actually pushed the balls with the butt end, or something.
The process of making these is pretty cool. I guess they take a blank stick and then they cut these wafer thin wood veneers into decorations or inlays. Then they steam them so they'll go around the radius of the sticks outside dimension and glue them to the blank. When the adhesive sets, they go all over the butt with an ebonizing compound until everything on the surface is covered, then wipe the compound down until the inlays show through and the surface is level, which is kind of backwards from new cue inlays.
Good luck in your search!
Steve