If you need a web resource for topo maps of the us you can go here
http://mapper.acme.com/
buttons for topo are on the top right.
The mapnik option would also be useful if you plan to use maps in any situation where Google copyright might enter the picture as it is open-source. Please do not construe this as legal advice but I believe that if you attribute it properly you can use them in games.
https://wiki.openstreetmap.org/wiki/Legal_FAQ
Quote:
3c. If I make something with OSM data, do I now have to apply your license to my whole work?
No. For example, if you have written a game or published an artistic map which includes OSM data, only the data is covered by the license. This is called a Produced Work.
|