Duplicates after importing to Iphoto...

In the Finder, hit command(apple)+F to pop up a search window. Change the parameters to something like, "Kind" is "Images" "All" (or whatever type of image you want to search for), and then to the right of that there is a SAVE button you can click to save the search parameters and ultimately add it to the side bar.

As for the duplicates, check the file sizes/locations of them or just open a few. iPhoto saves the image itself, makes a thumbnail, and a duplicate when modified. I don't know if those are all found in the search, though. If you messed with your library folder in the '06 version, or somehow did something you weren't supposed to iPhoto will punish you, and that could be the reason. If you never have done anything bad, it may have just felt like punishing you (I'm kidding in a way, but iPhoto has a mind of its own) or they may be the thumbnails and such.