IBMPCUG (IBM PC User Group) was one I liked.
I set up because I did not like the UKNet / Pipex duopoly that didn't seem to be to have even heard of customer service, and IIRC liked to claim copyright in all materials (eg USENET) that was routed via them... %-P
I imported and supplied Demon's first DNS server, a second-hand Sun workstation. I still remember carrying into their office and setting it up on a table for them. Cliff S was there I'm fairly sure...