Most everything else. There are a few exceptions, but most government sites are pretty good about clearly marking items that are not in the public domain.

If you want to get those colors that indicate elevation, that's called hypsometric tinting, and it will likely require a height map in addition to the satellite imagery or shaded relief. It seems like there was a pretty good tutorial somewhere around here about creating a hypsometric gradient and applying it to a height map in the Gimp (which is free raster-editing software. It is to Photoshop as Inkscape is to Illustrator.) It's fairly likely that RobA was either the author or discoverer of that tutorial. You can get height map information from NASA also, but it might take a bit more work to find what you need and get it to line up with your imagery.

Looking forward to seeing what you come up with!