One of our favorite things about reading other people's blogs is finding out about the blogs they're reading—and then reading them regularly ourselves. That's how we found the Book Cover Archive and it's blogging cousin, the Book Cover Archive Blog. The archives are loaded with gorgeous graphic design for those looking to get lost in cover art nirvana. The blog ruminates on all things book covers—including creating cover art for an e-book that would fit the proportions of the iPhone. Very interesting, especially the parts about using RGB vs. CMYK color and making black the dominant color so the cover could actually become a part of the iPhone front...if you're into that sort of stuff. Which we are.
So poke around both of their sites and you'll learn plenty, including who designed the cover for The Yiddish Policemen's Union and where to hit the motherload of NASA images for your next book on the space agency. Enjoy.