Thats the problem, there are few books that are current. The only one I know for sure is the
Adobe Premiere Pro CS6 Classroom in a Book.
Would you consider a video course? There are some excellant video courses on Premiere Pro CS6. The ones on Lynda.com are good, but there are also good free courses available. Take a look at the
Premiere Pro CS6 tutorials by Andrew Devis over on the Creative Cow site. Andrew Devis also has a set of
Encore CS5 Tutorials. Those will be fine for learning Encore basics.
You are correct that the trial does not allow Encore. It is downloaded and installed with Premiere Pro CS6, but you can't use it until the trial is converted to a purchased license. As far as quality goes, Encore is a professional level authoring application -- a side by side quality comparison of the final product with another authoring program isn't really going to tell you anything. You're going to be constrained to the DVD or Blu-Ray specifications and given the same source, menu structure, and data rate, the discs will operate and display pretty much the same. That doesn't mean all authoring applications are the same. They vary a lot in what features of the specification are available and what authoring capabilities are present. The first versions of Encore were a bit stodgy, but the current version is excellent. Should you not like how it operates, you can always use a standalone authoring package such as DVD Architect Studio. It just won't be integrated and support dynamic linking.