@OP
Don’t bother with Rothbard. ABCT has changed a lot in the past few decades (wouldn’t you be suprised if it hadn’t?).
You want to read Roger Garrison. Specifically, I think this article he published in HOPE back in 2004 does a great job of summarizing modern ABCT.
When you hear Bob Murphy, Pete Bottke, or most other modern Austrians talking ABCT, they are leaning on Roger Garrison. THIS is the place to start.
@Wheylous & Neodoxy,
Indeed, I do think Rothbard and Garrison contradict each other. Thanks for taking note. 
I support my argument in this old post:
https://forum.freecapitalists.org/t/paul-krugmans-great-leaps-backward-post/17014/26
It all boils down to the fact that Garrison’s theory predicts that investment and consumption will rise together during the boom phase. Rothbard’s theory does not. This is bad news for exactly the reasons Paul Krugman pointed out in his 1998 magazine piece.
http://www.slate.com/articles/business/the_dismal_science/1998/12/the_hangover_theory.html
And I honestly don’t think I am the only person to point this out. Pete Boettke of GMU makes a similar point in this blog post from a few years back (he doesn’t single out Rothbard by name but if you read MES or AGD you will see he is one of the “standard textbook” authors he is referring to). And if you read the entire blog post you will see that PB doesn’t think Garrison is the final word on the subject either. He thinks Austrian economists should continue grappling with this issue to make sure ABCT conforms to empirical evidence. He’s a smart guy.
Peter Boettke: Roger Garrison has tried to explain the possibility of comovement [between investment and consumption] due to the artificial nature of the boom which appears to violate the scarcity constraint…in the standard textbook presentation of the Mises-Hayek story we do not see comovement, but the distortion of the structure of production, which is then corrected during the bust phase.
http://www.coordinationproblem.org/2011/01/call-all-economists-lets-answer-a-serious-question.html