Map

As you can see, Lake Whitefish are located thought Canada and only in the northern most parts of the US. 

Where they like to live

Lake whitefish are cool water fish. They are found in a large number of inland lakes, and they have been known to enter brackish waters. The lake whitefish is distributed from Alaska and western Canada to the Atlantic coastal drainage of Maine and in New Brunswick north to Labrador. Lake Whitefish prefer to live in lakes. 

The Lake Whitefish like to live in colder lake temperatures which is why they are found in the northern more parts of North America