While I tend to use something heavier these days, I've done necks a few different ways by hand.
I've used spokeshaves, rasps, chisels, belt-sanders, angle-grinders, and my current weapon of choice the Fadal on necks. My observations are thus
I don't like chisels for the carved parts of necks, I just don't think they're the right tool for the sort of tight curves you end up dealing with. Belt sanders, angle-grinders (with low grit sanding disks), and spokeshaves all work great as roughing tools and can all be used to get all the way to the sanding stage if you're very careful, but they all lack the control and finesse of a rasp. With a rasp, you can take a pretty deep cut or a very light cut, and you have excellent control of both depth and shape of your cuts.
If I were doing them by hand now, I'd pick a roughing tool from the spokeshave/belt sander/angle grinder set and finish up with a rasp. I have gone 'start to finish' with both the belt sander and the spokeshave, but they were much slower than a rasp once it got to the near-net stage.
