Andy Quirt This site has some very fine blades.
Aoi Art usually stocks well priced low end pieces, but also has high end swords.
Buck T L PhD. Tsuka-maki, The Art of Japanese Sword Restoration. A must read for anyone who contemplates rewrapping a tsuka. I wish that it had been around when I was learning. However, that was back in the days before the internet, and I had to make do with slowly dissecting the knots, and drawing illustrations of their construction.
Buck T L PhD, Saya Lacquering How to put on a mirror finish. Another splendid article from T L Buck. Personally I usually use cashew lacquer rather than shellac, but the principles are the same.
Fred Lohman. Supplies sword fittings and offers restoration work. Very recommended.
Fred Weissberg. There are some excellent articles on this site, as well as items for sale.
Japan Sword An absolutely wonderful Japanese site.
The Japanese Sword Index. Rich Stein's online Nihonto Bible. This is the most comprehensive site on the Japanese sword. It is however so popular that you may get the 'Over quota' message.
The Japanese Sword Society of the United States. JSSUS. This organisation probably needs no introduction, given the number of publications that it has put out.
Moses Beccera A sword polisher and dealer in New York.
Moses Beccera's very informative article on sword polishing.
NBTHK (Nihon Bijutsu Token Hozon Kai): The Society for Preservation of Japanese Art Swords.
Nihonto Kanji Pages. An excellent reference on kanji used for swords and tosogu. Recommended for anyone who wants to learn to read tang inscriptions.
Nihonto Message Board A discussion board on all matters concerning Nihonto.
Northern Token Society. A sword study group based in the north of England.
NTHK-NPO (Nihon Token Hozon Kai). The Japanese Sword Preservation Society.
Robert Benson is a sword polisher and dealer in Hawaii. I haven't yet dealt with him personally, but his good reputation precedes him.
Samurai Kanetoyo. A sword shop in Japan run by Ping and Hiroshi Nakamura.
Shogun Oriental Arts specialises in WWII militaria, oriental antiques, and art items.
Walter Sorrells is an American smith. working in the forefront of Japanese-style swords. He has recently started to work with tamahagane.
And finally - and absolutely nothing to do with any of the above - there's my partner's businesses:
Black Earth beads. Ceramics.
Overspill. Haberdashery supplies, including metal buttons, wood buttons, novelty buttons, and bulk buttons.
The Occasional Purl. Textiles and dyeing.
English Gentleman. Vintage British clothing.