1) Take the initiative and name a place and a date. Then start a thread here with the place, time, and date here.
If you sit around waiting for someone else, it will never happen.
2) Collect names and numbers.
3) A few days before the meetup, confirm whether it's a go or a no-go based on whether a sufficient number of people have RSVP'ed.
You can hold a meetup without me. There have been meetups in Seattle, Chicago, and New York City without me.
It is helpful to provide instructions for how to get there in case it's complicated.
If it's a busy place, it helps to bring a sign that says ERE or something. You could also bring the ERE book and wave it around.
Most people tend to bring potluck snacks.
A meetup is a good chance to downsize your book collection...and other collections.
If you have any questions, it's good to write them down in advance. Otherwise, you'll forget to ask them.