Consider:
a. Judith Miller is a Washington-based reporter for the New York Times, specializing in WMD issues.
b. Valerie Plame is a Washington-based employee of the CIA, specializing in WMD issues. She also happens to socialize in circles frequented by the media.
My bet is that they knew each other. And I agree that Miller may well have been a source for others. And her source, in turn, was the wife of that renowned media hound, Joseph C. Wilson IV (if not Wilson...)
Add this:
c. Matt Cooper is married to Mandy Grunwald, a really close friend and sycophant for Hillary Clinton.