If you click on the Finder in your doc (the faces) you should get a window on your screen.
On the left side of the screen, under Favorites, is there a picture of a camera with the label Camera.
If so, double click on that.
Inside that folder you should see something called iPhoto Library. Do you see that?
Post back and let me know.
I would advise you to stop using the computer IMMEDIATELY and seek professional assistance. It's impossible to tell from your description what happened, and if the photos got deleted, every moment you use the computer after the deletion is a moment where one or more of those photos may be overwritten and permanently lost. If they didn't get deleted, the precaution is unnecessary, but if the photos have value to you, I wouldn't advise making that gamble.
I am going to add this in hopes that it saves someone the aggrivation I had to just go through. Let me start by saying that I am NOT an i-genius in any way, but I did solve a problem i couldn't find the answer to on here, and Apple wanted me to pay $50 to help me with. My experience for your assistance:
I had attempted to find the root files of my iphoto library. In doing so I went to
In doing so, it opened a version of iphoto that I had not been working with in the past. It also changes the dock shortcut to this iphoto address!
After about an hour, I stumbled upon another iphoto address, which is for a completely different library (ironically the one I had been using for the past 3 years). upon opening this library, it revealed all of my information as I had left it last, and also corrected the dock icon to open this version.
Going to this address and clicking that icon solved my roblem, and I hope it solves your too!