The present manual is part of a series available from www.agner.org/optimize as mentioned in the introduction on page 4. See manual 3: "The microarchitecture of Intel, AMD and VIA CPUs" of a list of relevant literature on specific processors.
A lot of other sources also have useful information. These sources are listed in the FAQ for the newsgroup comp.lang.asm.x86. For other internet resources follow the links from
www.agner.org/optimize. Some useful books:
R. C. Detmer: Introduction to 80x86 Assembly Language and Computer Architecture, 2'nd ed. Jones & Bartlett, 2006. Jones & Bartlett, 2006.
Good introduction to assembly programming
J. L. Hennessy and D. A. Patterson: Computer Architecture: A Quantitative Approach, 3'rd ed. 2002.
Good textbook on computer architecture and microarchitecture John R. Levine: Linkers and Loaders. Morgan Kaufmann, 2000.
Explains how linkers and loaders work
Henry S. Warren, Jr.: "Hacker's Delight". Addison-Wesley, 2003. Contains many bit manipulation tricks