Definitely join both fetlife and collarme but keep expectations in check. It does not have a search function that works for dating.Collarme has relatively few women and a majority of those are pro dommes. However, you can join groups with a local focus and groups focused on kinks that interest you.
I am uninterested in going to Fetlife munch's because of some social anxiety, but that seems the only way to maybe meet someone. There are not huge numbers of people and it is a long process to find the right people.
it is not specifically a dating site, but no one objects if you contact people that look interesting. Some advice : first of all, no *censored* picture for your profile picture. second, if you contact someone that looks like you someone might want to talk to don't be an ass about it. Mistymouse ( my nym on either site) I have had 0 luck with Collarspace and Fetlife.
be polite, and friendly, like you would be if you were to meet someone at a party. They make me hate myself more than anything, no one ever messages you.
And all of them are from hot young women, by their photo, looking for a slave to worshi8p them, although they live thousands of miles from you, are young enough to be your daughter, and won't reply to your messages, since they do not really exist. Church of Chains uses the same interface, but I do not know if they are at all related. It is international, mainly Dom Male and sub females but there are the opposite orientations too. So you have work cut out for you if you expect to be noticed at all.
But if you are a dominant male looking for more than playing in the semi-public scene with women who are already attached but allowed to "play," you are also facing extreme odds.