OHNO! ..........."They try to drag me back in"
thanks but no more months on end with limited sleep.
Owen you will need photoshop, a program like Global Mapper to process the GIS elevation data at an affordable price of ~$450.00, winzip to compress the files, the ability to create .bat batch files, gigabits of harddrive space and un-interrupted computer time to run the batch processing without having the computer for other purposes.
You need to scour/search the web to find suitable GIS DEM and Shape files for the geographical area you are interested in.
Owen get the CFS3 Terrain SDK it has all the definitions, and programs to process files once generated by global mapper.
You will also need the CFS3 vector processing program.
Once you have the CFS3 Terrain SDK, read the manual, take 3 aspirins, and if you have some understanding you can do it with lots of trial and error and redoes to fix riffs and bad data.
You will still need to put it into a theater and fly it to see if it is okay. Probably a 2 to 3 year solo commitment.
Good luck and good flying.