My iTunes is stored on an external hard drive. I have another external drive to act as a back up for the library. I also have a 3rd hard drive being used for Time Machine. Is it the case that the Time Machine drive will not back up my iTunes library because it is on an external drive? If that is the case, so far I have made a back up by dragging over the entire iTunes directory from one drive to another. However, this is quickly out of date (I tend to get one or two CD's each week). Is there any way to make incremental back ups or do I have to keep going as I am? Can I get Time Machine to do this for me?