Switching transistor off when current is supplied to it's base
You could use the switch to shunt the base current away from the transistor:



If you really need to apply base current to switch the LED off, you could use the transistor to bypass the LED:



However, this wastes all of the current that normally goes through the LED. A more power-efficient circuit would use another transistor that gets its base current shunted away by the first transistor: