Simple, what is simple to me maybe be impossible to others?
Have a look here
http://outerzone.co.uk/index.asp
This one is very simple. Will handle the weight. You did not say how BIG of a glider you were looking for?
http://outerzone.co.uk/plan_details.asp?ID=4100
The Bigger brother
http://outerzone.co.uk/plan_details.asp?ID=6201
You will need to build something to see how well it handles the weight. All depends on what type of glide rate you want. A brick with 12 inch wings has a glide rate, not a good one, but it does glide.
Of course it has to be mentioned, for all of the internet peeps, depending on where you are on the planet, will determine if you can do this.
Buzz.