It has been mentioned before that the original manuscripts to LOTR (and the Hobbit and some other stuff) is at Marquette University in Milwaukee, WI. Just wanted to mention that a fuller description of what the library has is here. [www.marquette.edu]
I’d love to see the unpublished epilogues, and Aragorn’s letter to Master Samwise. Looks like it is available to anyone with a photo ID and prior arrangement.