If you gave more information about what you're having problems with or what you need help with I'm sure we could give you more specific advice. If you've ever taken a Java class then I'm sure you've worked with Javadoc. If you haven't then it's pretty easy to figure out. In the "sunspotfrcsdk" directory (I believe it's in Program Files on a PC) there's a folder called doc and inside that is javadoc. In the javadoc directory open up index.html to access the specific on how the WPILibJ classes work. Also, netbeans with the FRC plugins contains a bunch of examples for controlling the robot. Use the New Project button to access them. Good luck!
EDIT:
Actually it's not in Program Files apparently, according to
this post.