My daughter is in France this summer and I used Brightroam to get her a local SIM card there. She has an unlocked RAZR and the card works fine. She forwarded her US number and the offer a toll free number for calls from the US. The number also has voicemail. The rate is about a third of AT&T for international calls.
Brightroam offer SIM cards from various countries. I'm fairly happy so far.