Did you try contacting the author(s) of the papers? In my experience, most authors are happy to hear about uses of their work (even if they are in a...
There are lots of tools out there that can do hillshading on available DEMs. QGIS is one option. A reasonable dataset for maps of the US is ETOPO2.
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Ohhh... so cool. I love it. very Tribal. Also reminds me of the Isle of Dread adventure module... the island shape.... Can't wait to see the finished...