restoring files on OS X 10.5.8

I'm helping someone out with their MacBook Pro. They accidentally deleted a good amount of random files through the Finder. They panicked when things weren't where they were supposed to be and moved everything from the Trash Bin to the desktop. Now, iphoto shows the thumbnail, but when you click it, nothing appears.

After the files have been moved FROM the Trash Bin to the desktop, is there a way to move these files BACK to their original location? I'm coming from a Windows background and figured this would be an easy task. Any help would be appreciated! Thanks!

If it's mostly iPhoto stuff, you may get lucky and just be able to move the directory structure intact. This post may help:

http://osxdaily.com/2011/08/30/where-iphoto-pictures-are-located/

Also, if it's just pictures: delete the existing photo library in iPhoto, then drag & drop the "restored" folders back onto iPhoto to create a new library - it will "import" the photos back into the correct locations and regenerate thumbnails and such.