This may be a stupid question, but you didnt really specify...is the book all your own work, i.e. your pictures, your writing etc. Just asking, because if it isnt and your using pieces from other peoples works or whatnot then thats plagarism and that is illegal, along with copyright infringements. just checking to make sure that your trying to sell ur own work not someone elses (even if you did piece together a bunch of stuff from a whole bunch of places). sorry if im going off on something that your not doing, just saying...all you said was that you had a book etc. not that it was your work.
and the cd would be way to simple to crack. but it does help as a deterent (you know like if something is slightly more difficult you deter some people from trying). so the real question would be whether or not to take the time to find it and put it on the cds. when your selling something and/or in a business...time is money