Radio Guide Australia gives you information on all radio stations in Australia.
If you have an iPhone or iPad with GPS you can get a list of all stations within range, with an approximate indication of the signal strength for each station at your location.
You can look up information such as station type/genre and transmitter details for any station, and also view the stationss website.
The search function allows you to search for stations by name, callsign, location or frequency. This allows you to look up stations anywhere in Australia, or to find stations without using GPS (for example using an iPod Touch).
Many of the stations can be streamed directly from the app. Note that streaming is not available for all stations, see ianstewi.com/station-list for a list of stations with streaming.
The app can also search for free frequencies that you can use for FM transmitters (such as those used for playing your iPhone or iPod over your car stereo).
This is a very handy app to have for anyone travelling in Australia.