Can't help you with the bite I'm afraid, but maybe I can help you find the werewolf enemy. First of all, they only spawn on a night with a full moon, and only in certain places in The Rift (for EP; for DC, it's Bangkorai, and for AD, it's Reaper's March).

Here's a map of Rift spawn locations: http://teso.mmorpg-life.com/become-werewolf-eso/rift_werewolf_spawn_location/ Once one of the spawns has been killed, they won't respawn in that location until the next full moon, so try not to kill it so other players have a chance to be infected as well. Just let it beat on you for a bit, then run away. You can check your Character sheet for Sanies Lupinus to see if you were successful.

I went looking for it but found nothing.