Ok, it may be a bad pun but I just came across this really good site and video with advice on sound recording in your films.
There’s some great advice here on audio perspective and mic placement.
It’s surprising what a huge difference audio can make in your films. It can have the effect of making your video captivating and slick or off-putting and cheap! There’s some great resources here at lights online film school blog with some more audio tutorials including advice on noise reduction and removing background hiss.