I do free two-hour Lightroom demonstrations here in Seattle, and towards the end of these, a question I often get is: how do I get my iPhoto images into Lightroom? I take this as as a good sign — I figure that what they have seen of Lightroom from my demo has convinced them to move to it. I’m not a Mac user, so rather than write my own post on how to get iPhoto images into Lightroom, I will refer you to Gene McCullagh over at lightroomsecrets.com:
Click here for Snow Leopard (a much easier process)
As Gene says, make sure you that in the Lightroom import dialog, you Copy and Add to Catalog, choosing a different folder to copy the images into. Once you have the images in Lightroom, you can use the Folders panel to reorganize them into meaningful folders. To create new folders, right-click on the folder they will live in and select Create Folder Inside… To move images from one folder to another, click on the first folder, select the images in the grid, and click on the thumbnail of one and drag to the new folder. To move folders, click and drag them within the Folders panel. Note that all this reorganization is happening on your hard drive, not just within Lightroom.