Where does Screensaver store images? I have only used iPhoto a couple of times by accident (preferring one of the many alternatives).  Each time, I carefully removed those images from iPhoto to the iPhoto trashcan and then emptied the iPhoto trash. Consequently, all the iPhoto sections appear empty:

But when I look at the screensaver, pictures show up when one of the iPhoto directories is selected (the directories can't be deleted in any way I know).

I'm assuming that the images were copied into a screensaver cache (or maybe a link was created). Where are these screen saver images stored?
BTW, I'm still running Snow Leopard on a beautiful 4gig iMac. Thanks!
After scrounging around in plist files (thank you find and grep!), I found the beginnings of an answer, but I'm still a little confused.

It seems that those pesky images have been lingering around (renamed, of course) in the following directory:
~/Pictures/

Deleted them, and now when selecting any of the iPhoto portions of Screensaver, I get the appropriate error message:


-Yeah, that's the ticket!

I hope others will have more details, so I'll wait a couple of days before accepting an answer.