This is probably the best online tutorial for creating reflowable text ePubs from InDesign CC:
There's also a matching one on there by AM on creating fixed-layout ePubs.
And there's an InDesign ePub forum for particular questions.
Yes, Liz's book is excellent, EPub Straight to the Point: Creating Ebooks for the Apple IPad and Other Ereaders: Amazon.co.uk: Elizabeth Castro: Books
and Chris Jennings: iTunes - Books - eBook Typography by Chris Jennings