The best lighting, if you are using indoors, are flash strobes or a remote flash. Using the one on top of the camera is OK, but it has it's limitations. If you can find a good backdrop and use some lighting off to the side you will get better results. Additionally, some of these photos you see that are exceptional or not just because of lighting, but how the picture is being shot. For example small aperture and extended shutter times, thus you will need a tripod to take these types of photos.
Take for example this photo. As you can see the light is coming from the top, not from the camera. It appears he might have used a slower shutter speed with a smaller aperture to enhance the details. Also pay attention to his depth of field (DOF) and how sallow it is. This tends to bring out the item or subject you are photographing.
Bryan