During routine fuel management enroute, the pilot had selected in turn the right TIP tank, the right MAIN tank and then the left MAIN tank. To complete his pre-descent checks, the pilot elected to leave the fuel selector on what he thought was the left MAIN tank. The pilot had previously notified a change of destination as Kingoonya due to the onset of last light. At about 1800 feet on descent, the engine coughed and stopped although the propeller kept turning. The pilot completed his trouble checks including changing the tank selection to the next position to the left on the selector panel which he thought was the left TIP tank. Engine power was not restored, so the pilot continued to concentrate on the forced landing. At a few hundred feet above the ground, the pilot recalled making a final check of the fuel selector position and found that it was in the OFF position. The left MAIN tank was reselected but the engine did not respond before the aircraft touched down. During the landing roll, the nosewheel struck a fallen branch and the noseleg folded under the nose cowl. The investigation established that the pilot had flown only five hours in the last three months, one hour in the last thirty days and had a total of only eleven hours on type.