I believe you're referring the Season 6 Supernatural episode, "Mannequin 3: The Reckoning".
To clarify some details of the plot mentioned in your description, the ghost, Rose Brown, didn't rip out any organs, nor did most of her victims receive any organ transplants from her. She was just killing various men who'd bullied her and unintentionally caused her death.
The only victim who had received an organ from her (a kidney, as you said) was her sister, Isabel, and Rose didn't mean to kill her; it happened inadvertently while she was attempting to run Dean over with a car.
Here's the relevant portion of the episode synopsis from the Supernatural Wiki page:
In Passaic, Sam speaks to Isabel Brown. She describes her sister, Rose, as quiet and shy - the sort of girl who was an easy target for teasing and pranks. Leafing through a photo album, Sam realizes that the janitor from Paterson also used to work at Salzman & Sons. Back at the factory, Sam interviews workers, and one in particular—Johnny—seems very nervous. That night, Johnny is attacked, but Sam is there to intervene. He confesses to Sam that he and some workmates bullied Rose by leading her to believe she had a secret admirer. When she arrived at an apartment for a supposed date, they revealed the prank, and, as she went to leave, Steve grabbed her and she fell, hitting her head on a coffee table and dying.
Sam finds out where they buried the body and heads off to salt and burn Rose's corpse. He calls Johnny, telling him the haunting is over, but he is mistaken. That night Johnny returns to his apartment and explains to his Real Doll that he is going to leave town, but she becomes animated by Rose's ghost and kills him.
At a loss, Sam speaks to Isabel, and she reveals that she had one of Rose's kidneys transplanted into her when she was 16. As a result, Rose's spirit can move around, able to go wherever Isabel does. Sam drives Isabel to meet with Dean, and the brothers try to figure out a way to put Rose's spirit to rest. Sam suggests Hoodoo as a temporary solution, but, as they discuss the option, the Impala revs up. Rose has possessed the Impala, and she tries to run Dean over. He manages to maneuver it into a wall, but Isabel is fatally injured in the resulting crash. As she dies, the spirit of Rose appears and apologizes before disappearing in flames.
And here's a transcript of the conversation you mentioned between the two male protagonists:
SAM: No. I think we have to go hoodoo.
SAM: Yeah, hoodoo.
DEAN: That's more of a band-aid, not really a cure.
SAM: It buys us a minute.
DEAN: All right, Louisiana it is.
ISABEL: Voodoo?! What the hell are you talking about?
DEAN: Actually, it's "hoodoo." It's a little different.
Supernatural - S06E14 - "Mannequin 3: The Reckoning"
A clip of that scene is also up on YouTube: