UPDATE: Second letter added, thanks for the tip Ardamir!
Currently available for bidding (to close on Dec 10th) are two letters from J. R. R. Tolkien. The first is a typed form letter from Tolkien dated 12th October 1966, with a crisp signature and added handwritten noted that says "If you use one of the modern steel bows, you should be developing a good torso!" It is currently bid up to $2310 at the time of this writing. The second is a two page hand written letter dated June 12th, 1925. No Middle-earth related content in it, but an excellent example of his handwriting and personality. As of this updated writing, it is bid up to $2716.