The Ozark Folk Center in Mountain View, Arkansas, will have their annual Tribute To Elton Britt Concerts on July 25-26. He was from this area originally. I rather imagine that if you want to hear yodeling, and lots of it, Mountain View is the place to be on that weekend!
Another Canadian yodeler worth listening to would certainly be Wilf Carter, or Montana Slim as he was usually known in the United States. He died in December, age 91. If you have access to Hank Snow's first recordings, he did a fair amount of yodeling early on in his career.