There are many, many, many resources out on the internet. Some of them are "real", but many are written as fantasy,
or AI generated junk, or are otherwise misleading. Of course, there is also a large amount of information targetting
more "kink" aspects of enforced male chastity, rather than chastity's role in more traditional relationships.
The following is a starter set of resources that the author of this guide has found useful.
Barrett, Key. Locked in Love. Independently Published, 2019.
Both the wearer and the keyholder may want to read some Testimonials.