Keep in mind folks, that the original graphic he'll be needing needs to be as close to actual print size or LARGER. Which is why Get may want to let folks know how large he will need it in either inches or pixels.
It's relatively easy for a printer to take an image that is larger than print size and make it smaller without image degredation...not the same the other way around.
Take an 300 x 300 pixel image (full color) and go to resize image and make it 10% smaller, then 20% smaller and so on and look at image quality. Take the same image and start making it larger in 10% increments and look at what happens. It gets unbelievably pixelated, blurred, and nasty pretty quick.