In the last months, the toolchain for using Haskell within Emacs has changed a lot, and has become a lot better. Apart from my additions to ghc-mod, new autocompletion packages such as company-ghc have appeared.
In the past, I've felt that there was a need for a comprehensive article of all the available options for Haskell development in Emacs, including haskell-mode, ghc-mod, company-ghc, HaRe and structured-haskell-mode. To fill this gap, I have written a tutorial covering installation, configuration and use of these tools, especially keeping an eye into making all of them work nicely when put together.
Hope it helps!