External hard drive and itunes music management.

So, all my music is on an external hard drive. I have ripped the tracks from CD's using windows media player in the format of mp3 files, I then bought an ipod/iphone/ipad and used iTunes to transfer the media. I have also spent a fair bit of time updating the track listings, genres, cover art etc, so it looks standard on my ipod. However, my question is, if I bought a new laptop/pc, would the information and man hours put into creating, what I believe, a good standard library, be transferred or would I have to start again?

Thanks in advance.