Backup Help!!

My husband said our computer was too slow due to the amount of digital photos on our computer so we got an external hard drive called Lacie. I dragged the iphoto library on it. It took hours to copy. Then I turned it off and unplugged Lacie. Then I went in to iphoto and deleted a bunch of pictures. Then I plugged Lacie back in and clicked on the link for iphoto library but it just takes me to my iphoto on my computer and all the pictures I deleted are not there. HELP!! Are my pictures gone? With the older iphoto you used to be able to click on the library and it would contain all these numbered files with pictures but now when you click on it, you just go straight to iphoto. I also saved my itunes library and when I click on that I can see all the artists and songs so why doesn't iphoto work???