Kristof had breakfast with the Wilsons at some Democrat Function in Seattle prior to his article. I think he even sited Plame in his article as "someone present at the meetings" referring to Wilson's meetings with the CIA regarding results of Wilson's Niger trip. Plame was at both meetings.
Information doesn't fall from the sky.....and wind up in the papers. Go back to that July 4th picnic and find out everyone that was there.
Don't forget....there were also two relatives of Joe's who knew about Valerie. (Why did Joe even tell these two relatives?) Valerie has never said how many people she told.
I still laugh everytime I think of Joe and Valerie living "in sin" at the Watergate before they bought their home NEXT DOOR TO CHRISTOPHER WOLF. Oh yeh...Wolf's law firm is out of NYC. Wonder if it's in the same building as Bubba?