That is thievery, and is illegal, and is not tolerated on this site.
Quite apart from the legal ramifications, when you are asking about these copies, you are effectively asking about how you can steal money away from members of this site:
Bryan Bashham,
Kathy Sierra and
Bert Bates (the 3 authors of the Head First book) are all members here, as is
Charles Lyons
Please stop and think about what you are doing. I assume that at some point in your future you would like to have a job. And you would, presumably, like to get paid for your work. If you are happy to take the work that others have done without paying them, then why should your boss ever pay you? Plus most religions will tell you that stealing is wrong.