Recently I've purchased an Apple MacBook Air 2.8. I've lots of content in my iTunes. From a few days, I'm thinking to restore Windows in my Mac afresh. If I restore Windows newly, my all-existing content will be deleted. That is why I want to backup my all iTunes content. I don't know the proper procedure to backup and also I'm a sound engineer. I have lot's of musical content in iTunes. I just don't want to lose it. Please someone help me to backup my all contents. Thanks.