Here is a list of some of my favorite ebook and design related sites.
Click Twice Design — For all of your eBook design needs.
Lynda.com — For all of your training needs, this site is the best.
InDesign Secrets — Lively discussion of all things Adobe InDesign, the premier page layout program.
MobileRead Forums — If you can’t find an answer to you e-publishing question here, you can’t find it anywhere.
Epub Checker — Validate your epub before you upload it to a bookseller. Word to the wise.
Three Press Consulting — As they say on their site “Digital tools for twenty-first century publishing.”
Kindle Direct Publishing — Amazon’s portal to their Kindle publishing site. What are you waiting for they still sell way more ebooks than anybody else.
PubIt! — Barnes & Noble’s epublishing portal. They sell the second most ebooks. Easy to sign up and get published quickly.
Smashwords — If you decide that getting published is more difficult than you thought, these guys can help you out.
Kobo — Kobo reader author’s page. Not as big as the others but still in the game.
ePub Zen Garden — This simple site gives you a look at one page of an ePub and how it appears with a variety of CSS styles applied.
Adobe Digital Editions — Must have download of Adobe’s epub reader.
Book Publishing Software — Great guide to book publishing software.
Calibre — E-book management software.
Pigs, Gourds and Wikis — May sound funny, but plenty of great epub help from Liz Castro.
Lulu — Lulu ebooks publishing.
Design Geek — Great tips and techniques for Digital Designers..
Sigil — Free open source ebook editor