Did a search on google and found a site that might help you out. I've seen some fine looking work on some bikes using gold leaf...might try it someday.
I do have a question about it myself. Let's say you want a gold leaf star, for instance. How do you apply it so it is the desired shape? I can't imagine that you'd apply it and then use a razor blade to cut the edges smooth. Would a guy simply mask off the shape, apply the sizing to the exposed surface, apply the gold leaf and then pull off the tape? I suppose since the leaf is so very thin it might act like paint would, and create a crisp edge when the tape was removed.
Hope this helps.