Texas Monthly has a piece about Christopher Alan Smith, who for the past decade has been creating original maps, mostly of Texas and Texas-related subjects. It’s been his full-time gig since 2008. Smith uses a mixture of pen-and-ink and acrylic paints:
I tend to follow the style of postage stamps and currency. I use a pen-and-ink stipple technique, which is a series of dots that create the illusion of halftones. Cross-hatching is another method, using lines instead of dots. I’ve also started using engraved wood to give the maps a layered, 3-D look. For example, on my Thirteen Colonies map, I illustrated the coastline on two layers of hardboard.