It is a perfectly reasonable question. I wish there were a reasonable answer... Like all small, volunteer-run organisations the UK Autoharp Association (UKAA) uses a variety of communication methods - depending on what was fashionable, or who was enthusiastic about what, at any given time...
There is a web site, which has just gained a new webmaster - so, hope, hope...
http://www.ukautoharps.org.uk/
There is a Facebook thing, which is not just for UKAA members, anyone can join, but you have to ask...
https://www.facebook.com/groups/Ukautoharps/
But, of course, many members of UKAA are NOT users of Facebook, and do not want to be...
So, there is a list of email addresses - which is not the same thing as an email list - to contact the wider membership.
There is a regular little journal - Autoharp Notes, which is actually rather good - which is available as a pdf file for UKAA members who do use email and the web. And a paper version for diehards.
Then there are the other email lists - real email lists - like Sorefingers (but that is for Blue Grass), and Cyberpluckers (but that is mostly US autoharpers)...
Do you detect a hint of despair here? Is the UK Autoharp Association really a secret society?
I am just a person whose intentions are good...
I get the Gargrave Autoharp Festival in place, and then I plod round places like Mudcat...

Patrick O'Sullivan