If you are a youth questioning your gender identity, you are not alone. There are many more like you than most people realize. There are other teens that feel the same way that you do. Your best source of information is the internet, or your local gay and lesbian center.
You can succeed and become who you need to be. It is not easy or cheap. You are very fortunate if you have a supportive family. I would suggest that you make at least one attempt to let your family know. I would have been able to start helping my child so much sooner if she would have told me sooner. Leave a book or pamphlet laying around by accident that addresses gender issues. Talk about a "friend" wanting to be a different gender than they appear or bring up the subject with your mother. If she freaks, then back off. Tell her you were just kidding, or under stress or going crazy. Then suggest that maybe you need counseling and see what happens.
At all costs, try not to get kicked out of the house. Stay in school, you are going to need a really good job to pay the bills involved in becoming comfortable with your gender. You can do it by yourself, but it takes longer and you may have to put it off until you can support yourself.
There is family you are born with and family you gather as you go along. If your family cannot accept You, don't drag them along behind you for years. It is a great weight on your karma. Take care of' yourself, find accepting friends, adopt other people who need family and then maybe someday your family will catch up with you.
You have the right to be the gender that you feel you are inside. You are not hurting anyone else, they are hurting themselves. You are not sinning, you are not crazy. You are not a second class citizen. You deserve the best, and if no one else will help you then do it for yourself.
Your sexual orientation is completely separate from your gender identity. Labels don't always work. You can feel attracted to men, or women, or both or neither. Who you are attracted to can change as you figure out who you are. Its OK. There is nothing wrong with you. Accept other people for who they are regardless of gender.
Your transition is your trip at your speed. There are some minimum times prescribed by the Henry Benjamin standards. But if it takes you 2 years to start hormones, or you stay in the androgynous stage for months, its OK. This is your trip and there are no maps.
Keep living. Don't put life off until you can have surgery. Enjoy the humor in life. Enjoy every day as another day in becoming you.