I am interested in any information you have on aircraft design on computer. Even though I'm not an Engineering grad, i would like to try my hands at designing an aircraft.
Nowadays, i hear a lot about aircraft being designed entirely on computers. I would like to know what type of programms are used(providing they are not"G14 classified"

).
The closest I have come to aircraft design is an interesting program called X-plane which i bought from £1.99 at my local shopping center. I was able to design a cessna 152 using the data from the POH and i was impressed. Apart from the usual shortcomings of PC sims, the engine and cntrol response was similar to that of the real 152 i fly.
I've heard that a real turboprop was designed using this program.
If anyone knows any similar (more "serious") program, please feel free to let me know. also is there any such thing as a computer based wind tunnel, i.e. i could creat objects in a virtual world and test their aerodynamic feature without actually having to do it physically?
Also does anyone know of a good amateur aircraft design website.
Thanks
Capt. manuvar