You know that Zune music store app which isn't on your Australian Windows Phone 7 device? It's still not there. However, Universal has launched its Getmusic service as a Windows Phone 7 app, letting you purchase music and merchandise from artists signed to the label.
The problem with a single-label service, of course, is that it doesn't necessarily give you access to a wide range of artists (though there are tracks from non-Universal acts on offer). Individual tracks on Getmusic range from $1.65 to $2.15, which is broadly in line with what you'd pay elsewhere.
Getmusic is a free download for Windows Phone 7 users (search for it in the marketplace). I'm not equipped with a Windows Phone 7 device right now; if you give the app a try, tell us what you think of it in the comments.