From the ground up? Well, there's always the source:

http://www.intel.com/content/www/us/en/processors/architectu...

For learning assembly? For MASM I enjoyed this book years ago:

http://www.amazon.com/Assembly-Language-Intel-Based-Computer...

For GAS something like this might be more appropriate:

http://www.amazon.com/Professional-Assembly-Language-Richard...

Patterson & Hennessy is used a lot in colleges to teach low-level architecture and assembly:

http://www.amazon.com/Computer-Architecture-Fifth-Quantitati...