All you need for a bit of BDSM fun, is a willing partner & a piece of rope.

To join in the 'scene,' there's sites like Collarme, & so forth- just look up BDSM in a good search engine.

I'm only conversant with the S/F scene, but it might be worth looking at places like the Fetish News site- bear in mind that some clubs etc prefer couples, they can be a bit prejudiced against single men.

Many people meet someone online, get to know them & then meet in person.