Those things are cool.....
There are plans available for these planes and a guy that is offering kits for 49.95 w/ most of the control linkage for the kit.
I saw the info on one of thr RC plane forums under the foamies sections.
I have one almost ready to paint and go testing,
I'm sure I smash it into a bouy before I get airborne :lol:
here's the link I have for the info on the plans.
So far the cost of material is 6.00 per sheet of foam I sheet does one boat.
I'm goning to make a second one but a little wider and longer.
Need to use foam safe CA to build
http://www.rcgroups.com/forums/showthread.php?t=380781
Here's the link for the gentleman to contact on the kits.
After building one I would say go with the kit build it and go fly, as the motor mount and other little things need to be made with the plans....but it's no big deal...afterall your build a boat hull out of foam.
I just prefer to build from plans....but that's just me.
http://www.rcgroups.com/forums/showthread.php?t=385089
Good luck