Nice idea, probably you know about this site already but if you don't....
http://www.fsglider.de/Some nice models there by Wolfgang Piper. Correction - a LOT of models..

There's also a links page (go down the list) and if you click on VET it has a way of catapulting the gliders into the air, haven't tried that though.
If you come across a way of getting a plane to pull you up let me know, that would be cool...
Hope the info was useful

Regards
Krigl
If you're bored of an evening - and you'll have to be - you can check out my screenshot gallery: Kriglsflightsimscreens
...HERE[center][img]http://www.simviation.com/phpup