Konkokyo main website and the English page
Konko International Center
Konko International Center(Old site?)
Konko Churches of North America
Konko Church of San Francisco
Konko Spirit - Church of Portland
Konko Church of Azuo (Japanese) and their English Site, which hasn't been updated in a long time but has some interesting reading.
Konko Church of Osaki (Japanese)
Konkokyo Amagasaki Church (page is Japanese, but there are some English language documents)
Konko Missions of Hawaii
Living With Kami (Olivia-Sensei's site)
Reddit r/konkokyo
Konkokyo Tengaku - music created for Konkokyo rituals, they also have a very out of date English site
Katori Konkokyo (technically a different religious branch, focused on Kandori Shigeemon)
Konko Zaidan, Konkokyo bookshop (Japanese)
Okamoto Shinki, Konko town worship supplies shop (Japanese)
Ogimachi Kyokai (Japanese only site, but they have resources like the entire 'Voice of the Universe' and lots of Japanese prayers accessible online.)
Konkokyo Followers site (Japanese only, link is to the 'Voice of the Universe' search page, but there are other resources here!)
Nakabaru Kyokai (Another Japanese only site with documents)
Fushimi Kyokai (Japanese! There are a lot of pages with interesting historical information that I can't read very well).
WaGaKokoro Research Institute (English site) And here's the Japanese Link
Wagakokology, has articles and links in both English and Japanese
Wagakokoronet 2! (Japanese only)
A Japanese Prayer Book, I have no idea who these are courtesy of and the site structure seems ... Precarious, so if you like them you might want to archive!
Another Japanese Prayer Book in epub format, ideal for phones and tablets. Courtesy of Konko Shuppan Shinsha, which as far as I can figure is a publishing house specifically for Konko church materials, like commemerative and memorial booklets.
Nagoya Kyokai graciously shares these materials in Japanese, including a children's prayer book.