I have a York Diamond fan forced heater and would like to know where to light the pilot light at?

Are you sure it has a standing pilot? If it does, turn the gas valve knob to "pilot", find where the pilot gas line, 1/4" in diameter, coming from the gas valve, ends. There should be a small hooded orifice. Push the big button on the top of the gas valve down and hold a match or lighter at the hooded end. It may take a while but the pilot should light. Keep holding down the gas knob for 15 seconds and then let it up. The pilot gas should stay on. If it doesn't stay on, repeat above. If it still doesn't stay on you need service. Then, rotate the knob to ON and turn up the thermostat. If you are not sure of the process, have a neighbor or someone else help you. Gas can be very dangerous.