Well you're in luck then. ArtRage should help you along nicely with that, since it allows you to import images as layers, tracings and references. If you're looking to draw people in a more realistic manner, try downloading some reference images of people off the internet and then importing those images as a layer in ArtRage (you could import them as a tracing as well, but I prefer layers because I can control the opacity and position better that way). Turn the layers opacity down and trace over some of the images, paying attention to how the body in each picture would differ from an image you drew free hand (things like foreshortened body parts, or limbs that are hidden when at a certain perspective) . After a few tracings, remove any tracing images and try to apply these differences to a free hand drawing.
Nothing is easy to the unwilling.