How to access playlists etc from previous install of iTunes

I recently replaced the HDD on my main studio computer with SDD, I have reinstalled windows (7) and most of my essential software.
I still have the original HDD on my desk and can connect it to the computer as needed.
This boot drive where the OS lives is one of three internal drives on this computer. My music library is on a different drive.
I want to install iTunes on the new drive and have all my old play lists and iPhone/ iPad backups etc. There must be a folder on the old HDD that I need to copy to the new SDD. Can someone please point me to directions on how to do this.