NO SOUND!!! HELP

Ok, I have no sound! It was working find then on day just stopped. Some people are telling me its the sound card and others the drivers. I know hardly anything about computers. Can someone help me figure it out? If its the card is it on the mother board for my computer? How much would that cost to fix? If its no cheap or easy then Im gna buy a new computer but I really don't want to spend the money if I don't have to.

I have a lap top Fujitsu N series Lifebook.

If you leave me directions, please step by step, don't assume I know b/c I don't.

Thanks