The retreat I went to a few weeks ago was in the back room of a fabric outlet store. The people there were so nice to us. It was basically just a sewing weekend. We didn't have lectures or anything, but we sure got a lot accomplished. Last year when the same group did the retreat there, they got to go to the Omnigrid factory and see how the rules are made. I wish I had been able to be there for that one.
If you get a chance, go to one. Or even if you have a group of friends that sew, organize your own. I did that one time. I used some of our timeshare time at a vacation resort, got a three bedroom unit, invited 5 other gals and we all took our sewing machines and had a great time.