Uhm, the swordfish stake comes from the Swordfishes and from one or two bulbs, I don't know that for sure though. But the sneaky things is that the Swordfishes don't always drop the Swordfish steak, they also drop normal meat, in which you may think that they aren't the right ones. I have no clue where to find these creatures though, I thought they were in The Veil, but I may be horribly wrong.