Shows have definitely changed! Today the biggest problem is buy/sell merchants. It was a problem back then too, but today it's become a major concern. So expect to see China stuff at the shows you signed up for.
Polymer clay showed up en masse about 10 years ago and died down just as quickly. I do shows with one person who is quite successful, but she has a specific product line. And she has cultivated a following at the shows. I've done shows with them for almost 10 years now, and they're still going strong.
As far as prices, what sold 24 years ago at $3 has gone up. Right now I would Google the inflation rate since 1990. That would be at least a starting point. At the shows I do, nothing is sold for $3.
Below is a website for a promoter I do a number of shows with. This is a listing of exhibitors who did a show in November. If the name of the exhibitor is in green, they have a website, so you can go and research prices of work today.