How to teleport after you've killed a villager?
You can track when a player kills a villager using the stat.killEntity.Villager objective-type:
/scoreboard objectives add KilledVillager stat.killEntity.Villager
And you'd run the following on a clock in order to teleport the player and then reset their score so that they aren't constantly teleported:
/tp @a[score_KilledVillager_min=1] X Y Z
/scoreboard players reset @a[score_KilledVillager_min=1] KilledVillager