Most people have heard of the atlatl (AT-latl). For those of you who haven't, it was the method of hunting in between the spear and the bow & arrow. It was simply an extension of the arm to help throw the spear, increasing range, speed, and accuracy. In this case, however, we are replacing the atlatl with a string. You just throw, following through, and the knot lets go of the spear.
is a good ebook on archery. It includes arrowheads, fletching, and making arrows. If you view one on making arrows, simply make the arrow longer than the Instructable says.