Treesize will show you where all your space is going. Just download the free version - that's all you need.
Good luck.
My hard drive is 1tb and is almost full with 24gb remaining. I have my external hard drive backup and it's at 275gb filled. I have 252gb of music and some pictures last than 2 gb and don't know why my hard drive is almost full. Everytime I'm on my computer I will lose 2gb of space and I have not downloaded or add anything to my computer. I just surfing the web and listen to iTunes. Any suggestion how to fix this? Thanks

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