as Mr. iab and Andy K suggest, it's not a bad idea to just throw together a ride, promote it through whatever methods are available, and see what happens.
I've been doing this for a few years and it's been a lot of fun! The group is a mix of local and semi-local folks. Some folks are new to the hobby, while others are veterans.
The important thing is to make everyone welcome, provide the opportunity to chat and get to know each other, and have a nice time.
Donuts help.
Steve in Peoria