You need the Android SDK
, on that page you have all the details on exactly what you need to install and how. The programming language is Java and if you've never touched a programming language before, the best book I can recommend is Think Java
. Your typical online tutorial
just tries to get you going as fast as possible but you won't really understand what you're doing, and you'll be relatively helpless when problems arise. Think Java is about acquiring an in-depth understanding of how to write computer programs and troubleshoot them.
You can skip the chapter on graphics though, as you'll not be using the APIs described in the book for Android.