This is a different approach. I recently released a first draft of learning assembly by example. It is not x86 assembly though, on purpose. Learning a better and easier to understand instruction set first, will get you through the basic concepts, from there other instruction sets, x86 included are often a matter of downloading an instruction set reference for the desired processor. https://github.com/dwelch67/lsasim
Normally googling xyz instruction set will get you a number of hits (instead of xyz choose the one you are interested in, arm, avr, 6502, etc). Ideally you want the vendors documentation which is usually free. There have been so many variations on the x86 by different companies that it adds to the mess. There are a lot of good online references though. For other families, msp430, avr, arm, mips, pic, etc, you can often go to the (core processor) vendors site to find a good reference. msp430, arm and thumb are also good first time instruction sets if you are not interested in the lsa thing. mips or dlx as well so I am told unfortunately I have not learned those yet. avr and x86 after you have learned something else first. Pic has a few flavors, the non-mips traditional pic instruction set is certainly educational in its simplicity and approach, might be a stepping stone to x86 (I dont necessarily recommend pic as a first instruction set either). I recommend learning a couple of non-x86 instruction sets first. And I recommend learning the 8088/86 instructions first, I can give you an ISBN number for the original intel manuals, can probably be found for a few bucks at a used book store (online). Lots of websites have the x86 instruction set defined as well, I highly recommend a visible simulator first before trying on hardware, will make life easier...qemu for example is not very visible nor easy to make visible. gdb's simulators might be as you can at least step and dump things out.
