while leather bound is nice, you can use a scrap book. it doesn't matter, it's what you make of it.
in terms of magick and God, magick isn't attached to one religion, it's working with natural energy to create change, hence the Christian Wicca community among others. if you can't speak with your parents, i hope you have someone to talk to like a priest or reverend. [assuming you're Christian] while i have met my share of close minded religious leaders, i've met more that are open to discussion. the point of a religious leader isn't to yell at you for an hour about why you're going to hell, or quote from a book, the person is their to help and guide you. you should pull them aside and ask if you could set up an appointment to talk. sit down and explain your dilemma and what they feel you should do. in terms of your parents, you should tell them, but do so at the right time, be prepared with answers, and don't let your emotions get the better of you.
my opinion with your situation, magick doesn't go against anything if you're using it to help others who ask. spells that force or do harm to others would be going against some religious teachings. if you live by a code of ethics, and do good, your God shouldn't be upset with you. at least my views anyway.