I found a light fixture that fit with my ceiling fan. I connected the white wire to the white wire and the black wire to the black wire. I put a light bulb in and pulled the cord... and nothing happened. The fan is connected to a wall switch, and yes... that was on, but the light won't go on. Any suggestions?

Does the fan still work? Was the black wire you connected to the light the feed from the wall switch, or one that is only hot when the fan is on? If the fan was sold without a light, the wire for the light may not be connected somewhere inside the fan housing.