Paul Shawcross, from NASA's Office of Inspector General, came to the agency's defense in comments published on CCNet -- a scholarly electronic newsletter covering the threat of asteroids and comets. Shawcross said the Saturn 5 blueprints are held at the Marshall Space Flight Center on microfilm.
http://web.archive.org/web/20100818173517/http://www.space.com/news/spacehistory/saturn_five_000313.html
Now, that said, all of the manufacturing lines, special tools, machinists with their know-how, etc to make the Saturn V are long gone, so having the blueprints is somewhat akin to knowing the recipe but having none of the ingredients.
Either way, I'm excited to see some of the new rockets that are being designed. Falcon Heavy should have its first test flight next year (fingers crossed).