Suggested are some items below with informational references of nihonto and tosogu.
The four below are a great start for the basics. All offer a valuable insight.
- Encyclopedia of Nihon-to by Markus Sesko – I suggest that you buy this Encyclopedia along with any of the following three…
- The Art of the Japanese Sword The Craft of Swordmaking and its Appreciation. By Yoshindo Yoshihara sensei & Leon Knapp
- The Samurai Sword A Handbook by John Yumoto
- The Sword of Japan by John Bott a co-founder of Nihonto study group (Japanese Sword Society of Southern California (Nanka Token Kai), great view point from a collector.