These appear to be free, I haven't confirmed it but I think you get a $10 credit for signing up too.
http://www.nomorerack.com/daily_deals/view/51297-safe_at_play_light___sound_books
I didn't get any referrals off of it and really didn't even pay attention to that part. Also sorry about the etsy confusion! I thought it was part of etsy because when you click on an item it will take you right to etsy.