When you turn your computer on do you feel your hardrive spinning, an unhealthy one will click or spin to fast but a dead one does nothing. You can open your case put your hand on it and feel it, if it does nothing it's fried.
I wouldn't pay to get it fixed they gonna charge you for all kinds of BS, this vid will show you how to replace a hardrive, they cheap and easy to swap.
http://www.youtube.com/watch?v=ZpLjV9uAZ1s