Another very good place to farm the blood is the ranger huts in Lesser Fay. It is a camp of about 8 wood elves or so, all very very green to a lvl 55. The best part is the camp has a very fast respawn. I would so in and wipe out the elves, and they would repop in less then 5 minutes.
They dropped the blood about 1 out of ever 3 or 4. I camped the spot for 15-20 minutes and got 8 vials of blood.
Loc is in Lesser Fay
Neg200 Pos1200 -maybe the other way around
A great spot for you dark elves to get your blood without killing members of your own race.
Thogor Wraithlance
55 Dark Elf Shadowknight
Sworn Few
Povar Server