For homes built on slabs, the line will likely froze where the pipe enters the home. For homes with basements, the line into the home likely froze where it passes through concrete block into the home.
Insulate pipes where freezing is likely to occur. If this is not possible, periodically turn on your water and let it run for several seconds, purchase a space heater to place in front of the pipes or purchase a heating coil that can be plugged in and wrapped around the pipes to keep them warm.
Try using a hair dryer and blowing warm air down onto frozen sections or into the opening of the block wall where the water line enters the home.