I'm not exactly a newbie because I've been using a MacBook for three years already but as time goes on my MacBook gets more and more cluttered with dupe files and images and I'm low on storage. I'm about to buy another internal and external drive. However, I am wondering just for future, how do I find and delete these dupes? For instance, I've been doing some Imovie work recently, and I've got all kinds of files related to the same footage. I have Quick Time clips, I have Imovie movies, clips, and I have disk image files, etc., etc., etc...I can't just start deleting because the Imovie clips depend on the underlying movie stored on the computer in order to work. I may choose the one related to the clips to delete and then I'd be dead. Also - just started using YouMail. Seems that the images for YouMail are constantly stored in images on my computer so each time I get a call, it creates an image and the image is saved, junking up my computer. Help!