Brexitometers started off as a spontaneous grassroots venture and are subsequently being organised by a couple of groups and individuals, principally Brexitometer HQ. And here's a map .
On Twitter they are @brexitometerhq and @brexitometerC
On Facebook it's BrexitometerHQ: https://www.facebook.com/groups/642186982847672/
This is more a discussion forum for future plans and sharing of tips and info. There is as yet no "page" on Facebook due to lack of volunteer time.