This map will display Virgin Mobile phone and mobile broadband coverage in different areas and expected performance when using an external antenna. The Virgin Mobile network uses the Optus network to provide it's customers with coverage to 97% of Australia.
It's important to determine whether you are covered by the new 900MHz 3G network or older 2100MHz network when determining what antenna is right for your Virgin Mobile service. Toggle between "3G Dual Band" and "3G Single Band" to find out which frequency band services your area - if you are not covered by 3G Single Band your area is 900MHz only.
http://www.virginmobile.com.au/coverage/