Like a lot of people have pointed out, there’s a huge correlation between drawing and carving / engraving. I’m convinced that with practice, some instruction, and the will, anyone can learn to draw. Unfortunately, it’s very much a learned endeavor, and takes time.
98% of the time I work out designs on paper. For me, it’s much easier than drawing directly on the stock, and you have a permanent design on hand. Don’t worry about the curves associated with the stock, it’ll work fine, and if you have to adjust it, you can.
While I would highly encourage you to pursue the drawing angle to this, you can certainly copy designs. Dave showed a great way to copy work, and would confess, I’ve done that plenty of times myself.
After you have a design on paper that is to scale (you can do that with a copier, i.e., enlarge/decrease size), use a fine tip Sharpie and trace the design onto a clear sheet of film. The film is used for overhead transparencies, and can be purchased at office supply stores. You can see through the clear film, which greatly aids in placing the design exactly where you want it. Tape it in place, then slip a piece of carbon paper under the film, and gently trace the design with a ball point pen. Here’s an example of what it looks like:
This is the image traced onto the stock, with some other elements I added later using the same technique:
This is a photo of the finished carving:
Ed