I visited “Yarra” just south of Goulburn earlier this year. However, I have since discovered a location that is officially designated as Yarra Yarra (as mentioned in the song) and was curious to see it so decided to call by.
The New South Wales Geographical Names Register lists Yarra Yarra at -35° 42′ 54.00″, +147° 27′ 4.00″. This is a field located along Yarra Yarra Road. Maybe one day there will be something more significant here (or perhaps there already is, but it’s well hidden).