we need more information to try to help you. what kind of printer is it? what have you tried so far? when you open the printer setup utility and try to add it, do you see it in the printer browser that pops up?
i recently bought a hp L7680 all in one printer. it works fine if i use usb connection from the printer to the mac. but if i run the usb to the apple airport extreme i can' get it to work.