The best (and cheapest) way to make international calls is to call over the internet using a programme such as Skype (check it out). You have to have Windows 2000 or XP though. Computer to computer is free, but you can call land lines after purchasing credit. Local calls here (Netherlands) using Skype cost me 1.7 eurocent per minute and my local telecom provider charges 5 cents.
You'll need a headset (USB handsets are good) or a microphone and headphones.
Check it out, it's brilliant!
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