This will be your real first quest of any length. First, head back out into the Blood Moors until you come to the Cold Plains. Now the Cold Plains will have an exit to the Burial Ground and to the Stony Field. Ignore the Stony Field for now. There is also a cave in the Cold Plains; it's the first of many side trips you can take for extra loot and experience. Go ahead and hit this before you go into the Burial Grounds.
Raven is in the Burial ground and is the baddie you need to kill. She is fast and pretty deadly to a low level person but the graveyard has a lot of areas that can confuse the pathfinding of the monsters so keep moving if you need a heal. Don't bother fighting her army of the undead; once she is vanquished her death will kill all the monsters in the graveyard. The Quest Log will tell you to go back to Kashya, but there are a few places in the graveyard itself to check out, the Mausoleum and Crypt. Clear those out for more experience and loot. Return to Kashya when you are ready. Once you've spoken to her, speak with Akara again.