In the standard rules all attacks with a bow do 1d6 points of damage. I wanted to add a little variety for characters who use bows heavily, as well as give the DM some options to use with NPCs and monsters who make use of archery in combat, so here's a collection of new arrows I devised to give your archers a little more flexibility. Enjoy.
Bone Tipped Arrow : 1d4
Used mostly by primitive cultures, including those of humanoids like Goblins and Kobolds, this arrow costs of a 3 or 4 inch long sliver of bone strapped to the end of the arrow's shaft. It's ineffective against any armor heavy than studded leather, causing armored opponents to simply ignore the attack, unless the archer takes a -4 called shot penalty to his attack roll to aim for an unprotected part of the body (if any, DM's discretion).
Cost : 1cp each
Stone Tipped Arrow: 1d6-1
Also used mainly by primitve peoples, this arrow is fitted with a head made of stone chipped into a suitable shape. The major improvement from bone arrows is that this variety can be effective against heavier armors.
Cost : 2cp
Sheaf Arrow : 1d6+1, -1 to hit
A thicker shaft and heavier head reduce the accuracy of this arrow, but give it a higher damage potential than the standard arrow.
Cost : 1sp
Whistling (or Screaming) Arrow : 1d6
Forces a moral check against creatures with WIS of 10 or lower carved channels in the shaft caused the arrow to spin on its horizontal axis, creating a high pitched screaming sound easily heard up to 1000 yards away
Cost : 5sp
Flare (or Flame) Arrow : 1d6
Causes additional 1d4 points fire damage if target fails a save vs. breath. Often used in the field by rangers and soldiers by shooting them straight up, hence the flare name.
Cost : 1gp
Stinger (Ceramic Hollow Tipped) Arrow : 1d6-2
May be filled acid or poison that is released on impact. these arrows shatter on impact and cannot be reused.
Cost : 1pp (does not include cost of acid or poison if used)
Frog Crotch Arrow : 1 point damage, Not very effective as a weapon, -4 to hit (generally against AC 10, but DM's discretion applies)
Successful hit allows the archer to cut ropes and cords. Used often by recon type rangers and archers involved in siege situations. The name is taken from the old 1E Oriental Adventures book, so don't blame me if it sounds a bit crude. The name is derived from the shape of the head, sort of a rounded v with the open end facing forward and sharpened along the inside edges, the arrow catches the rope and severs it.
Cost : 1gp
Note: I originally presented this material on the Grognard's Tavern forum. One response to that post was a query by the owner of that forum, who posts as Gutboy Barrelhouse, regarding how glass arrowhead tipped arrows would fit into my list, here's my response to GB:
Not sure what you have in mind with glass arrowheads. If you want something hollow that can be used to deliver a substance to the target, I'd say just use the stats I suggested for ceramic/hollow tip heads. If you want something solid, the stone tip head should work.