Best document / book for Mac hardware?
I'm sorry that you've had such a difficult time asking this question on Stack Exchange. I haven't been able to find a better/more up-to-date book, but most of Mac OS X is CPU architecture-independent anyway, and the book you're reading does contain an appendix that discusses Mac OS X on x86 hardware and the corresponding similarities and differences between PowerPC hardware:


  Appendix A, "Mac OS X on x86-Based Macintosh Computers," highlights the key differences between the x86-based and PowerPC-based versions of Mac OS X. Besides this appendix, the book covers the details of several key x86-specific topics, such as EFI, GUID-based partitioning, and Universal Binaries. Most of Mac OS X is architecture-independent, and consequently, the majority of the book is architecture-independent.