I personally decided not to tell my parents when I had mine done, although I (regrettably) wound up telling my mom because she got the impression I was saving my money for something and the ideas she was coming up with were worse than surgery for gyne, take my word for it! I made her promise never to tell my dad, and I don't think he ever knew. It did suck to go to the hospital and everything all alone, but it was just something I had to do. A friend of mine picked me up from the hospital and I spent the next week at my parents house and nobody suspected anything.
Now, back to your question- I can understand you not wanting to go through this alone at 19 years old. I was 21 btw. If you are nervous about breaking the news to them, you could try to drop subtle hints that you're up to something so that they will eventually come to you about it. For example, your running. It would be great for you to get into shape and that will also give your parents the first clue that you want SOMETHING to change about your body. After doing that for a while, and when you are more comfortable about the idea, you can make an appointment for a consultation, and give your parent's home phone number as your callback. Let one of your parents answer the phone, and somebody will say, "hi I'm such and such from Dr. so and so's office, is Scott there?" Legally, the receptionist will not be allowed to give any information regarding your appointment or they face a $250,000 fine and 10 years in prison under the HIPAA laws, so you should be safe there. It will be enough to get the ball rolling that somebody from a doctor's office is calling for you. That will probably get your parents coming to you with questions, and you can keep them hanging until you're comfortable.
On a side note, what are your main reasons for wanting to involve your parents? That is a serious question, I'm asking so that I can help you plan in advance to deal with certain reactions and find ways to get around it. Those are my main/ best ideas, let me know if you think it works for you or not.
Good luck