"But none of that planning, promoting of American music seems to happen at this place."

You do see planning for events like the FSGW Getaway, where there are a lot of people in MudCat likely to go.

The problem is critical mass, both in interest & location. If I want to try to get people together in Central New York, I'd do something on the Central NY Friends of Folk mailing list. If it's a Sacred Harp event, I work through the Shape Note mailing list. I get regular notices from someone about area Contra Dancing or I can go to Ted Crane's web page.

I'm sure there are similar groups for other locales and/or specific music interests.