I read a couple really helpful articles on Digital Book World that can help indie authors. The first gives some tips on how to design a cover optimized for Amazon, and all the other retailers where readers only see a thumbnail image. The second article gives a list of front matter and other tips on how to make a book look more like a traditional publisher made it. 
In the near future I’ll be covering a couple other tips on how to make ebooks look more polished–namely that the format of an ebook is incredibly important, and the most professional ebooks will have been inspected and tweaked to look good on multiple devices. This is kind of a pet peeve of mine, because the quality of an ebook can significantly affect someone’s reading experience, and the same ebook can look different on a Kindle Fire versus a Kindle paperwhite versus the Kindle app on the iPad. And of course they also look different on iPad versus Kobo versus Nook versus every other device.
Anyway, here are the links to the two articles I mentioned:
Sucessful Seduction and the Naked Truth: Rethink Cover Design for a Small, Small World
