Best ways to handle arrows and bolts:
1. Sneak. Sneak *everywhere*. It saves a lot of hassle even against normal enemies, and as mentioned, you can throw things while sneaking and never get noticed.
2. Get a good shield and a lot of armor, and train armor/shield user skills up whenever possible/safe. Talented Armor User as an initial first pick is really good for this, and four sets of iron chainmail plus seven hoods, an iron helm and an iron cap should do you well for head and upper body protection (presuming, of course, that you can get them... hoods are usually not easy to find in shops, though if you're willing to piss off human civs they can be easily garnered in towns).
3. Get as fast as possible. If you start out encumbered by your armor, train your skills until you either aren't or are so fast it doesn't matter. 1000 should be the minimum; any slower and the archers will assuredly get more than one shot for every action you take.
4. Get wrestling skill. It doesn't matter how fast they shoot if you jump out of the way. It also doesn't matter how fast they shoot if you can sneak up to them, snatch the bow/xbow out of their hands [free a hand by dropping either your shield or weapon, get in melee range, get to the wrestle menu and pick "Grab (x's bow/crossbow) with (free hand)", then use shift-I and pick the red (IIRC) weapon] and slay their weaponless hides. Even cutting off an arm isn't faster than this (people can shoot bows and x-bows one-handed).
5. Get really, really good with your primary weapon. If you disable/hack off both arms, or they fall unconscious from the pain, they can't shoot at you.
[ September 16, 2007: Message edited by: BDR ]