Last year, Google rolled out Hotel Finder, a service that was pretty useful even in its US-only version. Not only has the service expanded to include international destinations including Australia, it also now lets you search for a hotel by entering the name of a popular attraction and showing hotels within a given distance of that location by public transport.
Obviously that particular service is of limited use in Australia, since only a handful of cities offer public transport information via Google Maps (a perennial source of complaint around these parts). However, the ability to see hotels directly near a given location is still useful. The default travel time option for public transport is 20 minutes, but you can tweak this.
Having identified potential hotels, I suspect I'd be searching via other tools to see if I could score a better deal and to get other reviews. Finding a decent hotel that's convenient and affordable requires effort, but Google's tool isn't a bad place to start.