When you are new to artificial lighting, you might not have the equipment to tackle complex multi-light setups, but that does not mean you will not be able to produce professional results. This great video will teach you how to create professional portraits using just a single light.
Coming to you from Miguel Quiles, this excellent video tutorial will show you how to take professional portraits using just a one-light setup; in fact, Quiles takes his using only a speedlight. You can actually put together a fairly nice kit for only about $200 using a Yongnuo speedlight and Westcott softbox. Personally, I think it is much better to start learning artificial lighting with a single light, as you will be better able to understand and gain an intuition for things like modifier size and falloff when you are not dealing with the complexity of multiple lights. Notice that since Quiles does not have a light for the background to control its brightness separately from the subject, he uses the distance of the background from the light to control the amount of light that falls on it and thus, its relative brightness. Check out the video above for the full rundown.