Even with digital cameras there are some basic skills every photographer should have, or you will always be caught out by situations where you can't the camera do what you want or the pictures don't turn out the way you expect.
You should be totally familiar with these elements long before you begin your shoot. They should be second nature; simple mistakes with these elements can leave you with shots that are uninteresting or unusable and, unlike landscape photography for example, you may never get the chance to re-shoot them!
Some of these topics are potentially vast, and have been covered in great detail elsewhere, so where appropriate links to further reading materials are included.
If you want something to take things further then I would heartily recommend downloading Tony Page's excellent ebook "Take Better Digital Photos". He shares my philosophy of keeping things simple and shows you how to make the most of whatever equipment you have - rather than giving you an endless shopping list of cameras and lenses.
With 135 pages and 130 photos there is enough material to take your photography to the next level. He even offers a money back guarantee, so you can't go wrong really.