I just ordered a copy of The Dharma Bums and On The Road for a friend. I will be presenting them to him along with a copy of The Beat Handbook. He's paying for them - I'm just doing the grunt work. He's never read any Kerouac and wants to be able to connect with my book.
Of course, the versions of Kerouac's books I am providing him are not the exact versions I used. Having those versions along with my book would be the complete package: the reader would be able to bounce back and forth between Kerouac's books and my book to identify passages I reference.
So, in case you want to own the trilogy, below are the covers of the versions of The Dharma Bums and On The Road (both 1976 copyrights) that I used in writing The Beat Handbook. Any version of Kerouac's two books will do, but having the below versions is the ultimate way to play "treasure hunt" with my book.