Hypnobabies Homestudy

So sorry if this has been posted previously but I was hoping someone may be able to answer a question of mine. I'm a FTM and am wondering if it's necessary to purchase the entire home study packet or if having access only to the CDs is enough. My sister still has her CDs she offered me but is unable to find all the pamphlets that accompanied it. If I choose to go only the CD route are there any other supplemental materials you would recommend I purchase? Thank you