I'll do you one better, sir. In my own book on George Hoyt's Civil War career, I detail in the very first chapter the "Yankee" conspiracy to break Brown out of prison. Mine is not a "major book" by any means, but it is a book, which means that I have picked up your gauntlet to, as you said elsewhere, "Quibble with me in print, and I mean in books and articles." As I mentioned before, this information has been available for a century. Renehans's "Secret Six" and McGlone's "John Brown's War Against Slavery" both mentioned it in the last two decades. McGinty's "John Brown's Trial" noted it most recently in 2009. The best Brown biographies of the century note it. I note it in 2012.
However, since the conspiracy went nowhere, the fact that it is not mentioned in the majority of Brown books means nothing. Consider that a conspiracy of silence on the part of Yankees if you must. I rather consider it a judicious use of editorial discretion.