We use Java, and it works fine for basic and advanced topics.
We get our new programmers on our team started with the attached documents. The first one gets you started, and the second one talks about many of the important classes.
If you ever want to find more about a WPIlibJ class (while using netbeans, not sure about eclipse), just right-click and click "go to source" to see the base code. This is useful for developing your own classes to suit your needs.
If you want to use Eclipse (as opposed to Netbeans), go
here.
Be advised, that since the platform FRC uses is based off of either jdk 1.3 or 1.4, there are several advanced features that you can't use. But shouldn't be a problem at all.
Welcome to FRC!