What kind of bolts do you want to smith to use against the bane of Evil Vampires in Dawnguard, Do you want Explosive and Ice like bolts... Poisonous bolts(without alchemy)...

bolts or quarrels on real crossbows can be made to carry all sorts of erotic and nasty stuff to discomfit the enemy without magic.
eg,a glowing coal that sets fire to things,
poison.
acid,
animal crap to spread diseases,
bolts could carry more than normal bow arrows because they were much heavier and crossbows were very powerful,if cumbersome.

and im sure theres stuff thats deadly to vampires that can be put in them in this game,although i prefer to flatten them with a big hammer!

is there stuff ingame deadly to svckheads? ive never bothered as ,well i refer you to my hammer comment made some moments ago. cheers

Just give me some silver bolts, and I am good to go ( I am assuming that the vampire hunting Dawnguard use crossbows as standard equipment, why not make them up to the job).
As to the other stuff, there are plenty of poisons already, made or found/purchased, sometimes it seems to me poisons got more love than spellcasting.

Ice Bolts and Poison Bolts wouldn't work well at all against Vampires, since they're Resistant - Immune to Frost, and are Immune to Poison. Explosive Fire Bolts should work well on them though, since they're Weak to Fire.