1501 seems to build there bot every year using monocouque, pretty much just sheetmetal and rivets. (about 1,600 rivets

). Its great, and its what the aircraft industries use. It takes some practice, but our tools are pretty much a drill press, pneumatic metal shears, and a tabletop belt sander. We also use some chromoly tubing, and that will reguire some welding. But monocoque can easily be integrated into a kitbot frame.
go to huntingtonrobotics.org for some inspiration. Click on the photos icon at the top, and then select 2008 build season. (you may have to hit the back "more photos" button on the lower left hand side. It may be back a page)