from my experience:

http://www.callingcardscheap.net
900 cards, check rates below:
Canada 0.4=A2
Mexico 1.0=A2
United States-0.3=A2
Bangladesh 3.5=A2
India 6.2=A2
Pakistan 9.8=A2
Sri Lanka 6.4=A2
Call to Asia Pacific
China 0.4=A2
Hong Kong 0.4=A2
Indonesia 1.9=A2
Japan 0.4=A2
Korea - South 0.4=A2
Malaysia 0.4=A2
Philippines 4.5=A2
Singapore 0.2=A2
Taiwan 0.4=A2
Thailand 1.6=A2
Vietnam 9.8=A2
Call to Europe
Denmark 0.4=A2
France 0.4=A2
Germany 0.4=A2
Italy 0.4=A2
Russia 0.9=A2
Switzerland 0.4=A2
United Kingdom 0.3=A2
Call to Latin
Argentina 0.4=A2
Guatemala 2.9=A2
Honduras 8.3=A2
Peru 1.0=A2
Venezuela 0.4=A2
Call to Middle East
Egypt 4.5=A2
Lebanon 3.6=A2
Morocco 7.7=A2
Saudi Arabia 3.9=A2
http://www.callingcardscheap.net