Board Thread:Skyrim/@comment-10539363-20130607033223/@comment-98.19.158.86-20141209180231

Easy source for blood is listed here by me (NOTE: YOU NEED THE DLC for these sources to be possible to get):

Orc: cracked tusk keep.

Falmer: dwemer ruins.

Dark elf: readers at solsteim.

Wood elf and high elf: just start the dawnguard storyline before starting DIPLOMATIC IMMUNITY and kill thalmor soldiers after they kill malborn. That's both high elf and wood elf.

YOU NEED THE DRAGONBORN AND DAWNGUARD DOC'S TO MAKE THIS STRATAGY POSSIBLE.