They're not available as e-books, but if you're going to read Conan, I recommend Gollancz's two-volume Conan collection from their "Fantasy Masterworks" series:
http://www.amazon.co.uk/The-Conan-Ch...2165227&sr=1-2
http://www.amazon.co.uk/The-Conan-Ch...2165283&sr=1-3
These two volumes contain all of the Howard's Conan stories, as Howard originally wrote them. Many other Conan collections either include material from other authors, or have re-written versions of Howard's stories that have been altered to fit someone else's ideas about Conan. This set does not - it's the original versions of the stories.