Use the freely available GeoMapApp to save the area of the world you want to print. Then use the geo-stl program to convert the file into a 3D printable *.stl file.
Screenshot:
Examples (on Thingiverse):
Windows version 1.4
Linux version 1.4
Pro version now available for free.
- More file formats accepted (.png,.tiff,.asc,.xyz,.grd, and .nc)
- Can use with GeoMapApp and OpenTopo files
- Advanced Options