You hear the draft inducer motor but the ignitor won't come on right? Therefore no heat. It could be something as simple as a rollout switch popped out because of spider webs in the vent pipe or rusted burners etc. It may be that the draft inducer pressure switch hose has a blockage so take tha hose off and blow through it. That draft motor pulls a vacuum on that switch and kicks on the ignitor. If the hose is blocked the pressure switch won't work and the ignitor won't come on. Then get your flashlight and find all the little reset buttons and push then in. Don't let em bite you. You get your finger in between two hot wires and OUCH! Make sure you clean the furnace good. Most of the time it is the stack chimney rollout switch that needs reseting. These furnaces are mucho complicated amigo. If you are uncomfortable about messing with it you better get a pro over there. If you ain't got the money then be careful. It could be something as simple as the ignitor blown but I doubt it. Clean the furnace. Find the resets. Their are usually 1 on each side of the heat exchanger, 1 on bottom and top of heat exchanger and one in the vent pipe. Their could be a fuse on the board too.