dedicated to the discussion of the chinese internal martial arts of xingyiquan, baguazhang, taijiquan, related arts, and anything else best discussed over a bottle of rum
Zhang Yun, The Art of Chinese Swordmanship, on Wu style jian thru Weatherhill books, is my favorite sword book. Scott Olson and Yang Jwing-ming each also have a taiji sword book out.
If you haven't already read it, I would highly recommend: The Way of Energy by Kam Lam Chuen. A great read with a lot of exercises you can start working on right away!