Treasure Hunters HQ has posted on this very issue. Treasure Hunters HQ has a whole collection of posts to make your game more interesting and flow better than ever before. Everything from shields to magical unguents. Go ahead and follow them, the HQ is full of good ideas.
Ah... back to the point. Arrows. Tracking arrows on character sheets simply burns holes in the sheet. It is annoying and subject to abuse. Many years ago, I realized that player's will cheat on ammo more than any other thing. Why? Because, it is annoying. To avoid it, I tended to have the players encounter lots of arrows, either because the enemy had them, they were working from a fortification, or they had a natural pause to collect up their used arrows. Some players will want to roll a number to see if the arrow broke, but that is as exciting as my other pet peeve, save vs. drowning.
After a while, I decided to impose a rule that if a player rolled a 1 with ranged weapons, they fumbled the quiver and dropped all of their arrows on the ground. Picking one up, pulling one from a target or returning an arrow shot at the player takes time, a single action. If the character doesn't take any other action, they can refill a quiver in a single round. It seemed reasonable, since the standard has been changed from a quantity to have something or don't have something.
My primary issue with running out of arrows as a DM is, the rules don't take "out of ammo" into account. It is assumed the characters have a functional method of attack, and a certain quality of weapons. But if the requisite ammo is missing, they have neither. Suddenly striping the characters of missile weapons isn't really accounted for in the rules. While a good DM will give players and characters time to reprovision, the DM really can't account for 4 character's missile counts on the fly.