First of all, I must say only the countries listed below are support free international phone calls we are talking about here.

Argentina	Australia	Austria	Belgium
Canada	Canary Islands	Chile	China
Czech Republic	Denmark	El Salvador	Finland
France	Germany	Greece	Hong Kong
Hungary	Ireland	Israel	Italy
Latvia	Lithuania	Luxembourg	Mexico
Netherlands	Norway	Peru	Poland
Romania	Slovakia	Slovenia	Spain
Sweden	Switzerland	United Kingdom	United States

Okay, if you live in one of the above countries, let’s go the easy way.
Of course you need to install Google Talk (usually called GTalk). After successful install GTalk, click the “Add” botton to add a friend. If you want to call phone number 123456789, just add “123456789@talkster.gtalk2voip.com as your friend. Be remember the phone number is a digital string include area code but without any space or dash chars.
After add the phone number, you’ll get a confirmation from Talkster with instructions. And then your friends will use Talkster phone numbers to call-in to be connected with you.

Is it better than skype?