itunes folder on external hard drive

Hi,

I had my music folder on an always plugged in external hard drive as the files were bigger than the macbook's own hard drive. I've gotten a new mac and want to know how to get the new mac's itunes to recognise the folders in the hard drive. the new mac does not have enough space in its hard drive to import and then export back to the hard drive and I kinda don't want to lose the meta data (play counts etc) from the old mac. How do i do this?