So where can you go beyond Microsoft's old copy of Combat Flight Simulator if you want to fly jets? Well, besides a joystick, you are in the modding and open source communities. People are just maintaining and skinning stuff. Amazingly creative. Starting at "Sim-HQ":http://www.simhq.com/_air/air.html#reviews you can see a whole series of reviews for something called the various "engines out there. "Combatace.com":http://combatace.com/ is another dedicated site. It turns out all the serious flight sims are just based on 1990s engines and have rereleased modifications. The big ones are:
"Thirdwire":http://www.thirdwire.com/ is one example of an online only simulation company. Their Wings Over Israel for instance recreates the 1967-1982 wars. It is $30 for a 246MB download. They have similar titles like Wings over Europe. It uses a common engine called Strike Fighters: Project 1 that Thirdwire maintains.
"EECH/EEAH":http://www.simhq.com/_air10/air_313a.html which stands for Enemy Encounter: Commanche vs. Havoc and Enemy Encounter: Apache vs. Havoc which is a helicopter simulation. There is a whole community at "EECHCentral.com":http://EECHCentral.com which maintains mods. "Razorworks":http://razorworks.com maintains the code still and it is open sourced essentially. You still need a copy of the EECH CD which is kind of amazing really.
"Falcon 4.0":http://www.f4hq.com/ is a very realistic F-16 simulation. So realistic, it is actually incredibly hard to fly. This is now 30 year old technology, so its not surprising managing the radar isn't very automatic. Still a very rich community of folks keep at it. It was the first PC game I really fell in love with! "f-16.net":http://f-16.net has a huge number of manuals for Falcon 4.0 and real world information too.