[1] http://www.amazon.com/Computer-Organization-Design-Fifth-Arc...
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.
https://www.amazon.com/Computer-Organization-Design-MIPS-Arc...
https://www.amazon.com/Computer-Organization-Design-RISC-V-A...
I guess as of today we know which one to get.