This week's book giveaways are in the iOS and Features new in Java 8 forums. We're giving away four copies each of Barcodes with iOS: Bringing together the digital and physical worlds and Core Java for the Impatient and have the authors on-line! See this thread and this one for details.
On http://java.sun.com/javase/reference/api.jsp you can find links to the full documentation of all major JRE releases. The release notes of each one have a section titled "What's new" or some such; that should provide what you're looking for.