SIM Card USA/CAN with good coverage
I am rinding across CANADA and the USA (Halifax, Québec, Montréal, Chicago, Denver, California etc.).
I need a simple SIM-Card, just for telephoning and maybe for Google Voice (never heard of it until I read thisi thread).
Is there a good provider with reasonable rates? Since I don't know much people overseas, I only need the SIM/Mobile Phone to make reservations or in case of an emergency.