I have a very nice microphone (a Yeti-Blue USB) and Audacity, but no matter what I do when I record it sounds halfway decent (though not as good as I would hope) in audacity, but muffled and far away and generally terrible in game.
Does anyone know of voice acting for Skyrim tutorials?

What exactly do you mean? Audio should sound identical ingame, with the exception of your audio environment. (Echo in large caves, etc)

Upload a sample of your audio. I've spend a huge amount of time looking over and enhancing thousands of lines of dialogue, so I can at least give you a base estimate of how good the audio is, and what problems it may give you.