You almost always want to spend more on hardware then software because your software can only do so much for you, especially with audio. As for a good cheap mic that really depends on what you consider cheap, and the type of videos you make would determine what type of mic you need. The blue yeti will probably be fine for you starting out unless you do live on stage performances or music production. Its a USB mic so you don't have to worry about midi boxes or analog cables, it has 4 different sound settings, and the gain knob can be set for a wide variety of volumes. The Blue Yeti costs about $120.00. As for software you would probably be fine with Audacity (which is free) or whatever video editing software your using as they typically have enough features to edit audio very well.