I also make custom signs to order from as little as 5$ per sign. Price of course varies depending on what you want. A rough guide follows, but its better to contact me directly with details of what you are looking for. If I can sell the sign in my store then the below prices can be reduced by 50%.
1. Existing mesh, existing image with custom text - 5$
2. Existing mesh, new image with custom text - 20$
3. Existing mesh, new image, new material (wood, metal, stone, etc) with custom text - 30$
4. New mesh, new image, new material with custom text - 50+$