Originally Posted by ChiliConCarnage
You should be able to get a prepaid SIM from a local provider.
I second this. It's actually pretty simple to set up an account in foreign countries and will be your cheapest way to call home without doing Skype or FaceTime over wifi. Even then, you probably wouldn't spend more than $14 per day on the phone time unless you really like to talk. Just get a basic unlocked gsm phone to take down there and find a vendor for the SIM once you arrive. Or you can buy the phone there too, but you may pay a little more for it.