The Japanese community has been writing a book for months and it is now published -- "Hello Nostr!". It is available at the online shop, it will also be sold at the “技術書典” held in Ikebukuro.

https://techbookfest.org/product/veGeNq1tNkYFfWnZWgEC72?productVariantID=u5RZNM5e77xHH97c65PCx9