Relatively minor, combat-centric update: bullets to be shot with (what else?) a sling instead of stones. All the kinds of bullets work essentially the same way: they are easier to aim and hit harder than stones. The difference is how much easier and how harder.
1. Metal bullets: realistically these should be made from lead. In H&H, any metal will do, for simplicity's sake. Before you start flaming, yes, I know tin is too light. Working with what I'm given here.
2. Clay bullets: I don't think there's anything I should add about these.
3. Pebbles: these spawn along river and lake banks as a low-difficulty herb spawn.
4. Bullet pouch: works nearly identical to a quiver, but sits on your belt (What? No belt slot? One of the slots you put pants in, than). Around 40 metal bullet, 30 clay bullet, 20 pebble or 10 stone capacity. Quality increases it, but not by much. A bag is a bag. Made with leather working skill, some leather and string.
Some links to show how slings are awesome:
Wikipedia tells about sling ammo http://en.wikipedia.org/wiki/Sling_bullet#Ammunition
A very interesting guy talks about slings: http://www.youtube.com/watch?v=covH4voKukw
And what you shoot from slings: http://www.youtube.com/watch?v=lU87f5o8vMg