Help, all of my iphoto images disappeared after I saved an image from an email as a library!!! Can I recover my photos?

I was saving an image from email to iphoto, and somehow it was saved as my iphoto library. All of my photos are now gone, there were hundreds, and the one image I just saved is the only one there. Where are my photos??? Don't they get saved somewhere on my hard drive aside from being hosted iphoto? I have a MAC AIr and iPhoto '11.