Does anyone know if there are special clamps available for joining scale model fuselages together and if so ,where I might find them Thanks, John

How do you want to join them? Do you mean clamps for temporarily holding something while you glue the halves together, or do you mean some sort of internal clamp that will be used as a permanent holding solution?

Visit you local hardware store. The same clamps used for making such things as furniture and picture frames can be used for scale modeling. Just look at the selection they offer, there are many different styles and shapes. Much of the tools we use are taken from other hobbies and applications. Don't limit your resources to that of the scale modeling venue.

plain old rubber bands work wonders on the odd shapes

John, you're only limited by your imagination. Rubber bands, clothes pins, and binder clips are a few things you might find just lying around the house. On a trip once, I used the clip on a motel room skirt hanger.

There are small spring clamps at places like Harbor Freight that have a 1" capacity and run around 6 for U$1.99, I've also picked up a miniture ratcheting clamp at one of the big box home improvement stores, be carefull you can crush a fuselage with one of these. Years ago a buddy gave me some RC aircraft building clamps that were an L shaped clamp with a sliding jaw that was held in place by a rubber band.