I'll try to help. I have PSE3, although I've recently switched from iPhoto to iView. But I have a pretty good feel for iPhoto.

In order to use Spotlight or Smart Albums effectively, I strongly suggest that you use keywords to tag your photos. To add to your list of keywords, go to iPhoto>Preferences>click on Keywords>click the Add button. In order to organize my digital stuff, I use tags that describe the type of element (Backgrounds, Ribbons, Frames, etc.) and color (Color-Blue, Color-Red, etc.).

Then in order to tag your digital stuff, click on the picture, then go to Photo>Get Info. Click on Keywords, then check off the keywords that you want for that digital element.

After you've tagged your photos, you can specify Smart Albums to organize your elements (to see all your Backgrounds, for example). You can also use Spotlight, which will search for keywords. Spotlight will also search the comments box. You might want to use that box to type the designer's name, the kit that the element is from, or whatever.

Let me know if you have more questions. I'd be happy to help.

Kelly