I accidentally completely deleted my system preferences, not only from my dock, but when i click on the apple menu and choose system preferences, nothing happens. I do not have my install dvd, but i am on 10.6.8 snow leapord. So please, if anyone can either give me a link to a download for system preferences or give me some knowledge on how to get it back, it would be much appreciated. Also, I somehow lost my app store and address book on my back, and I REALLY need everything back. So please, somebody answer me. ASAP