Arbo, the little alluminum landsailors with the terrible looking sails that you see laying on their sides are called Manta Twins. They are what we have, they're an out-of-the-box deal so that everyone has the same boat. Its nice because the old beat up ones that we have can still beat the new ones. The little one with the sail that looks like a windsurfer sail is called a Fed 5, they're faster than the mantas, but there are fewer. The big boats mostly come out of austrailia and new zealand i think, if htey aren't completely hand built. Umm, I'm not sure how you contact the manufacturer of the mantas, but there is some dealer info here
http://www.nalsa.org/It really is a blast, but not nearly as many events every year. No one else I've talked too but us uses them on the beach, partly why ours look beat up. But there are still fun on beach. Takes about 10 minutes to get used too if you have sailing experience, and then you could easily compete with the fastest guys out there, thats part of what makes them so fun.
If you have a dry lakebed close-by, this is a definate weekend toy.