Welcome to the Mac.
You can easily name your photo's in iPhoto.
Launch iPhoto and click on the picture that you want to name. In the lower left hand side of the window there is a column with the names of all your folders in it. Underneath that, in the same column there is an Info square. If you cannot see it, locate the Blue "I" along the bottom of the window, on the left, and click it. The info square should appear. From there you can name your photo.
When you loaded you pictures from your camera to iPhoto, you put all the JPG files (the actual pictures) into iPhoto. They should be there in the Pictures folder.
If you cannot find them, you can Export your picture, the one you clicked on, by going to the Export function on the top menu bar. It's location changes depending on what version of iPhoto you are using. In iPhoto 5 it is under Sharing. Click export and export a JPG to the desktop.
Hope this helps a little
New to mac and need some help with iPhoto. On one of the fishing forums I'm on they use photobucket to add photo's and I sure am having a hard time finding the photo's I want to add to photobucket. How do you name them and locate them? Keep it simple please.