This is going to sound strange, but can you draw? I'm not really good at it soooo. :roll: If you are, draw out a small drawing and take it to say Staples and have it blown up to the size you want and then use that as a template.
Another thought! :shock: Have you seen a picture like you have in your head? If so, you can do the same thing. Blow it up in black & white and trace it out.