In Reply to: what about calling aus? posted by newhoneymooners on Friday, 5. March 2010 at 20:07 Bali Time:
I think you're confused about what "roaming" actually is.
When you have a SIM from an Australian provider, it will work in Australia no problems. If you take your Australian SIM overseas to use, you will need global roaming activated, then the SIM will connect via a provider in that country that has a deal with your home provider. You get charged high rates for making calls, and you also get charged for receiving calls - but you do get to keep your usual home number.
If you're buying a SIM in Bali, it will be a whole new account with an Indonesian provider, including a new Indonesian phone number. Roaming is not needed as you are using the SIM within Indonesia. When you call your kids in Australia, you'll be making an international call - roaming has nothing to do with it.
When you buy a SIM in Bali, they will set it up in your phone and activate it for you. Ask them to write down for you the numbers to put in front of the home number you wish to dial. They should have a "cheap calling code" you can use for cheaper international calls.