>>My questions are how fast, or slow should I take things? How much should I strech and how far should I push it when I do strech? How many classes a day should I take? What kind of classes should I take? Should I strengthen my muscles just by doing ballet or are other forms of exercise good to build lean muscles?<<
Your body is like a long railroad train. It takes a lot of energy to get it moving, but once it's started, it can move right along. What that means is that at your age, you have the ability to take class almost all day long, but if you try that right away, you'll end up hurt and actually lose time. Start with one class every day. If you are already at that level, move it up to a couple. If you find yourself chronically fatigued and keep making mistakes on things you know how to do, you are pushing too hard - so back off. If you take more classes than you can deal with physically or mentally, you are just wasting time and money. You court injury as well as teach yourself bad movement. Quality instead of Quantity! Practice doesn't make perfect - perfect practice makes perfect. One guideline you can use for all kinds of exercise activities is the 10% rule that states you can increase whatever you are doing 10% a week and probably remain injury free.
Stretching is an activity that cannot be rushed either. It takes years to acquire the kind of flexibility you want. Never stretch ballistically (bounce). Approach each stretch slowly, and never go into the realm of pain. You should be thoroughly warmed up prior to stretching.
If you want to dance ballet, take ballet classes (duh). Don't waste your energy studying other danceforms until ballet is second nature to you. After a couple years of just ballet, you might want to take jazz or modern as a refreshing alternative to the rules and strict procedures of a ballet class, but wait until then.
Reading between the lines, it sounds like you may be acarrying some extra poundage, so regular aerobic exercise is even more important to you than other dancers who are at desired weight. Dance may make you sweat but it doesn't count as an aerobic activity because you don't maintain an elevated heartrate for a sustained time. That means run/bike/swim should be part of your day, too. Some dance teachers thinking running is bad because of the looser hip joints dancers acquire with their turnout. I love to run and have no problems that can be attributed to combining it with ballet, but tread carefully there, because all I can offer is anecdotal evidence based on my experience. I know of no empirical studies about running dancers (any PhD candidates need a dissertation topic?)
You also need to hit the gym and do some resistance work (weights) to improve your upper body strength. This will help when you get into partnering, as well as give you basic muscle tone. As a dancer, you do not want a bulked-up, "Arnold" body so lots of reps with light weights should be the basis of your program, not lifting heavy metal.
>>I am dancing right now at a great studio in LA, but their ballet program isn't that great. Does anyone know of a teacher that'll work with someone my age, but is very serious about learning the ballet? <<
If their ballet program isn't great, then it isn't a great studio for you, no matter how good their other programs are. Go online and search for a new studio, open up the back pages of DANCE magazine, or look in the yellow pages and find a new place, complete with someone who can act as master teacher/mentor/coach to keep you on track. It might take some looking, but anyplace as big as L.A. has the right place for you.
Good luck and please respect those of us who are spending our time to answer your questions by keeping us up to date on your progress.[/i]