Wow, this page was last updated when I was quite into MSFS-5, and after buying an add-on, Rallye Tour du Monde, and started logging flights, with some little 'pictures', wowee ....
This is the trav-000 current link to that ...
But through this link, http://www.flightgear.org to FlightGear Flight Simulator, I found a rich world of people enthusiastic with flying, in all its forms. There are 'release' versions available, but if a lot of interest and some programming knowledge then get the SOURCE, and compile it yourself!
Then you will see their rich dataset of earth scenery, together with a vast array of airports, runways, taxiways, etc., and you can download blocks at a time, or have it download as you fly to the new location - sort of online update.
This is the trav-999 current link to that ...