i'm a beginner, and i use 4 point lighting - two 500 watt tungstens up top with shoot-through umbrellas, and two foot lights of 150 or 250 watts, depending on how much light i'm looking for. i haven't had any dark or ugly shadows to fill, but then i have a very controlled area i shoot in unless i'm outdoors.
http://samys.webphotoschool.biz/ the free lessons here actually helped me out a LOT. i really spent time absorbing them, and they saved me a lot of time later.