Tony, with my other hobby, competitive growing, up to several hundred of us meet up every year at an International convention, it was held in Niagara falls for a decade, it has now been moved to Vegas. There are informative presentations, a lot of talk between friends that have only talked online, or only talk online all year, we all share info, tips techniques and generally have a great time for one weekend a year, we eat drink and laugh around the clock.
There are people that travel from Europe, but most are from the US, traveling many hrs by car or plane to get there.
There is a cost involved, the cost of the seminars, and the cost of the hotel room, but it is well worth it, and a lot of fun.
This isn't out of the realm of what could be done with Wine Making talk members, who wouldn't spend, let's say $90.00 or so dollars to hear seminars from possibly (obviously this is all hypothetical) Daniel Pembianchi, and other well know Authors and award winning experts in their field.
I can almost guarantee that the major manufacturers would send their experts to talk about the benefits o using their products and equipment. I'm sure that they would send samples as well.
Offsetting the cost of the hotel and conference rooms could be done by offering tables that vendors and manufacturers could display their goods, and even sell their products at the convention.
I've been involved in these types of events at various levels for years, and I'm invited to speak at several grower club meetings every year.
To set something up, A first annual Wine Maker Talk Seminar, or Amateur Wine Makers Seminar would be hard, it involves a lot of work, and a team to get it done, but I think it would be a blast!
Just a thought..