hard drive back up?

is there a way to back up your itunes library to an external hard drive? everywhere i look it says cd/dvd back up. i have about 30 gigs of media and i want to do monthly back ups (adding lots of stuff lately). is there a software or anything i use to back up to a hard drive? thanks in advance for any help.

Try SuperDuper

I second Superduper: It does a daily backup of all my stuff when I get home from work in the evening to my external harddrive.

My Macbook holds our master music and photo libraries, whilst my girlfriend's only has a subset of our media. She mainly has documents and files from university that she needs backed up, so I use a free Moxy account to back up roughly 1,6GB of her stuff automatically.

It saves me from having to hook up the external drive to her Macbook and doing it manually and backs everything up in the background without her having to do anything.

thanks. ill give it a try.