Mary Schneider has been mentioned a couple of times so far. I have no idea who billed her as the Australian Yodeling Queen and am in no position to comment on whether the title is deserved but she is a formidable talent. She may not appeal to everyone but surely some folks will like what she does. She is well represented on youtube.

Clarinet Polka

Mockingbird Yodel

This is a different Mockingbird Yodel than is sung by Carolina Cotton and other country and western swing singers. A search on youtube for Mockingbird Yodel will turn up several fine Aussie yodelers including Angela Hayden and Dianna Corcoran. You can also find Wanda Jackson and the Cowboy Yodel.