A good start for anything regarding the Japanese swords, Rich Stein's pages are excellent.
https://www.japaneseswordindex.com/
The Viking Sword site had been a very early visit I made, along with Stein's pages and other sword related resources.
Another portal is Fordham's
https://sourcebooks.fordham.edu/sbook.asp
A large collection of links here, another very early bookmark in my lists
http://www.sirclisto.com/
Cheers
GC