That is pretty cool signage. Unfortunately, we're stuck with digital photos taken from the tee box for most of our courses around here. Updated signage would really make our courses seem nicer.
I design t-shirts for a disc sport clothing company. You can see my designs at Sink-o. It's been pretty limited thus far because we only have a one-color press. Soon, we will upgrade, and I'll be able to do a little more involved designs. The shirts have been well received in our area. Maybe it will raise some awareness for disc golf and get more people out on the courses.
I have been offering to do caricatures on golf discs. I've gotten an OK response, but I haven't been go-getting after it. I start with a caricature drawn to the right size on a piece of paper (you can trace the disc onto the paper for the right dimensions), and then I find some method of transferring the drawing on to a disc with the stamp removed (I use the Mr. Clean Magic Sponge and a little elbow grease to take stamps off - Star and Champ and the like are the best). In a pinch I'll just run the side of my pencil lead all along the back side of the drawing, and then position it in place on the disc (with tape) and re-trace the drawing, so that the graphic will show up on the disc for tracing over with Sharpies.