Maps using Gnomonic Projection

I would like to find or generate a variety of map images in
various world areas that use the Gnomonic map project (Great Circles
are straight lines). I want to use this as a background for a
simulation that uses a rectangular grid for visualization. I want to
do no calculations (e.g., distance) more complicated that the Great
Circle Distance formula.

Generally, I want to spend most of my time on the simulation
rather than on selecting GIS data and generating a map.

My other desirements are:

- Short learning curve for tool (if one is needed)
- Little time required to find the right data (easily accessible
within the tool)
- Quick and easy to generate graphic image (e.g., JPEG or BMP) of
desired map area
- Easy to select area and scale of map
- Free or cheap tool and data

Do you have any recommendations on a tool/data or other source
for this?

Do you think there is a better way to approach this (besides
Gnomonic projection)?

Thanks, Alan