I'm under 18, so right now I don't pay any taxes. I had a paid app and I also just started advertising, so eventually I may be making income. I don't want to be evading taxes, so I want to know how to go about paying them. I know that both Google Wallet Merchant Center and Admob put my Social Security number on a tax form, so will I just be notified by them when taxes are due? Or do I need to create an LLC or SP?
Lets say i'm under 18, so right now i don't pay taxes
What's the connection? The fact that you're minor doesn't make you "tax exempt", you pay taxes just as anyone else.
i want to know how to go about paying them
You, or your parents, file tax returns on your behalf and pay your taxes. If any are due, that is.
will i just be notified by them when there due?
No, its your responsibility. They might send you some tax forms (1099), but even if they don't - your taxes are your responsibility. The IRS has detailed instructions on who and when has to file tax returns.
Or do i need to create a LLC?
These are legal entities for limiting liability. In most cases they won't add any tax benefits, and in fact may cost more in taxes (especially in California).