Having been, since 1980, a bookseller at and/or co-owner of independent bookstores, I am never going to be a fan of Amazon. Barnes & Noble is a little too big and corporate for my tastes, although they're still better than the online behemoth. Give me an indy store any day.
Trouble is, when you're trying to sell self-published e-books (and you can't begin to figure out the ridiculous Google Books interface), you are mostly stuck with going through the giants--Amazon, B&N, and, through, Smashwords.com, places like the Apple, Kobo, Diesel, etc.
But I've become aware of an online store I mentioned a few days ago, called DriveThruFiction.com. This place is great, if--like me--you love fiction that wouldn't have been out of place in the days of the pulps. Drive Thru sells primarily sf, fantasy, and horror (and, through related sites, RPG materials and comics!).
I have put up offerings in PDF, Mobi (Kindle), and ePub (Nook) formats so far. The books available there are epic horror novel The Slab, and short horror fiction collection Nine Frights. They can both be found from my ILT Publishing page--at low, low prices! Take a look.