the US Geological Survey offers a map service with aerial imagery: https://viewer.nationalmap.gov
I made a test by downloading images of 1m NAIP. Creating TFW coordinate files was easy with the given information about edge coordinates and resolution.
Geoconvert can work with these data, the positional fitting is excellent. The big advantage of these NAIP images is the consistent image coloring and quality.
Of course the scenery is flat, but how to add buildings is already solved and can be done subsequently.
If you are interested, check out the nationalmap viewer.