Interestingly enough, I'm only a year older then you, and interested in the same stuff =P.
Well, development anyway, not neccissarially for Apple computers though. However, I did have one in the past, and I discovered a few things.
First, Java is very good with cross-platform development, meaning you can code an app in Java, and it'd work on both a Mac and a Windows machine.
If you don't like that, then you could use C++, and code specifically for Mac machines.
Either way, I'd recommend using Eclipse. It's an amazing IDE, naturally with Java, and works with C++ if you use plug-ins.
On to tutorials. Now, I'd recommend using the internet! First, it has answers to just about anything you could think of. First, have a long-term goal. Learn the basicas... variables, input, output, ect... syntax for whatever language you want. Then get more advanced, until you can do something epic awsome =D