I guess as of today we know which one to get.
All of us came from software backgrounds, never having touched any hardware description language.
To get started I'd recommend reading Computer organization and design by Patterson and Hennessy (http://www.amazon.com/Computer-Organization-Design-Fifth-Edi...).
For the VHDL part, all we had available was this small basic VHDL compendium (not sure if I can redistribute it), open source github repositories from friends and classmates, as well as the always helpful vhdlguru.blogspot.com
So i'll reccomend following one of the open lecture series posted above :)
If this is absolutely the first time you are looking at architecture, http://www.amazon.com/Computer-Organization-Design-Fifth-Arc... by the same authors might be a easier entry point.
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