You need to go to your race's home city graveyard to do this quest; if you are a Blood Elf you must go to Silvermoon City, Orcs and Trolls to Orgrimmar, Undead to Undercity, and Tauren to Thunder Bluff. However, you can get the items from the Chapman at any GY. Once you have the bread and one of the marigold flowers, talk to the Cheerful (Your Race Here) Spirit who is standing next to its portrait to do the quest and receive Macabre Marionette.
The SMC graveyard is just east of the southern entrance to Falconwing Square. Run out of Silvermoon and follow the wall across the dead scar, and Catrina is at 48.50 in Eversong Woods.
The UC graveyard is in the Ruins of Lordaeron across from the SMC teleportation orb, and Catrina is at 68.12 in UC.
The TB graveyard is at the base of the elevators leading off from the middle bluff, Catrina is at 56.18 in TB.
The Org graveyard is on the left side of the road from Org leading to Razor Hill, Catrina is at 47.18 in Durotar.