Woodward also stated that he had communications with 3 high ranking Bush administration officials of which 2 are current members and one is former and that the Plame info came quite casually and unauthoratively from the "former" offical, which would let Rove off the hook.
This should not be hard to figure out. Given the nature of his book, Woodward only talked to top people. I don't think Novak's source was high up, given the clues Novak has given out, but Woodward's may very well be Powell or Tenant.