While this isn't strictly EPUB, a lot of people who frequent this forum will be interested in a new Lynda.com video by Kevin Callahan: "Creating Fixed-Layout eBooks for the Kindle" starting with InDesign assets. Here's the direct link:
Creating Fixed-Layout eBooks for the Kindle | Lynda.com
If you're not a Lynda.com subscriber, you can get a 10-day trial.
Here's a link to InDesignSecrets.com single free video from the series, and a sample of videos (not free):
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