I can only give you pointers to JavaEE 6 books (overall).
Beginning GF3 is an OK introduction to JavaEE 6:
Oracle Tutorial (formerly SUN tutorial) for JavaEE 6 is another OK one (reviews were meh, but you've got limited choice so...)
I saw Amazon has the print edition and another one to be in stock by mid 2012 (Advanced Java EE 6...)
Here's another book covering Java EE6 (intro):
Seems to cover Servlet more than Apress book (first book).
You probably would need to know JPA 2.0 (ORM) as well.
And some more "best practices/real world-ish" tutorials:
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