LAD has moved. Please check out http://groups.yahoo.com/group/LightAircraftDesigner. It's a user-group so you'll need to sign up as a member. But, as they say, membership has it's advantages. The software itself has been upgraded several notches, and there are a bunch of files there with sample aircraft to help in the design process.
Best of all, it's free and open-source. You can see how the calculations are done, and make changes if you wish to.
Why did I move it? Because I HATE ANGELFIRE. Don't you also find all these ridiculous pop-ups annoying? It's impossible to take pride in one's website with all this outrageous advertising.