What resources would you recommend to get started with?
It used to be good, but it is not any longer thought of that way.
And I agree with your basic point that building one is the only to gain true understanding.
https://news.ycombinator.com/item?id=1727004
https://code.google.com/p/letsbuildacompiler/
(It looks like there are several more or less complete C versions.)