I agree with Brion about Kirk’s Randolph, with the caveat that he makes Randolph pretty much a Catholic–an idea that Randolph himself could have been expected to find either humorous or insulting, I think. Then again, he found many things either humorous or insulting. You can glean an idea of the outline of Randolph’s career from Kirk’s book, and particularly read his selection of Randolph’s speeches. William Cabell Bruce’s two-volume Randolph biography includes extensive excerpts from Randolph’s writings too; he’s just hard to resist.
Henry Adams’ Randolph biography is only appropriate for people who already know Randolph well, as it is essentially Adams family retribution against the man who dubbed John and John Quincy Adams “The American House of Stuart.” Do read it in the end, however, because Adams is a fabulous writer.
My favorite John Randolph biography is THE EDUCATION OF JOHN RANDOLPH by Dawidoff. It’s detailed and even-handed. The best short description is the introduction to him in Coit’s Calhoun biography, where she paints him pacing around the House chamber followed by his dogs and a slave.
Kirk edited Randolph’s letters to Dr. John Brockenbrough, a leader of the Richmond Junto whose house later became the Confederate White House. That book gives the flavor of Randolph’s personality. Again, however, read Dawidoff first. Bouldin, his nephew I think, wrote a Randolph biography over a century ago. It’s not what you want.
I’m not just yammering: these are all on my bookshelf. Randolph is my favorite congressman. He was funny, brilliant, and a good friend, and he had the right principles. Of course, the laudanum sometimes clouded his brain.
One more thing: in the illustrations section of JAMES MADISON AND THE MAKING OF AMERICA, you’ll find a sketch of Randolph that had never been published before (except by me in an obscure magazine many years ago). Take a look at that, and you’ll see what his illnesses did to him.