There is no such thing as truly free, full-function telephone service. Somebody has to pay for the cost of acquiring and managing the phone numbers, handling the calls, and dealing with customer support. Google Voice isn't free -- Google makes money if you spend more time using as many Google services as they can convince you to use, and thus send you advertisements.
There is no free 911 service. If there was, it would probably route emergency calls to a guy named Fred, who, when he's feeling up to it and isn't hung over, would look up your city on a map, and then call their police or fire department. Providing a highly-reliable connection to the country's E911 systems costs money.