David Corn's article in The Nation was the first one that claimed that Plame was a covert agent. And the source for that article was almost certainly Joe Wilson. It appeared two days after Novak's article.
And Wilson wrote a piece for Corn's The Nation, back in Marcyh 2003. Where he railed against the "new imperialism" of the "neocons" (Jews).
And Corn claims that he's not been called to testify, right? Yet when the investigation began, Gonzalez is quoted as mentioning just 3 journalists, Novak, Royce and Phelps (the last 2 work for Newsday). Link