Hi Racer
I think you will have to do a bit of research into what systems are available out there.
The decision on what would be best for you depends on how much you can do yourself. Are you handy with a soldering iron etc, have you a back ground in electronics etc. ?
In my opinion I think one of the best systems/ product range is from
http://www.betainnovations.com/ .
These products are very easy to use and connect up.
They allow all different types of combinations of switches rotaries etc.
I have been using a Plasma USB unit for a number of years and I have never had any problems with it.
I think Leo from Beta has also been developing some s/ware to interface into Flight Sims such as Falcon etc which could be just the thing you may want to use to make the sim control various leds etc..
Check it out. Keep us up to date on your progress.
cheers
chuck