The seeking after knowledge of future or hidden things by inadequate means. The means being inadequate they must, therefore, the supplemented by some power which is represented all through history as coming from gods or evil spirits. Hence the word divination has a sinister signification. Asprophecy is the lawful knowledge of the future divination, its superstitious counterpart, is the unlawful. As magic aims to do, divination aims to know.Divination is practically as old as the human race. It is found in every age and country, among the Egyptians, Chaldean's, Hindus, Romans, and Greeks; that tribes of Northern Asia had their shamans, the inhabitants of Africa their mgangas, the Celtic nation their druids, the aborigines of America their medicine-men — all recognized diviners and wizards. Everywhere divination flourished and nowhere, even today, is it completely neglected. Cicero's words were, and apparently always will be, true, that there is no nation, civilized or barbarian, which does not believe that there are signs of the future and persons who interpret them. Cicero divided divination into natural and artificial. Natural (untaught, unskilled) included dreams and oracles in which the diviner was a passive subject of inspiration, and the prediction that from a power supposed to be then and there within him. Artificial (taught, studied) comprised all foretelling from signs found in nature or produced by man. Here the diviner was active, and the divination came apparently from his own skill and observation. This division is almost the same as that given by St. Thomas with respect to the invocation of demons: divination with expressinvocation of spirits, embracing dreams, portents, or prodigies, and necromancy, and divination with tacit invocation through signs and movements observed in objects in nature, such as stars, birds, figures, etc., or through signs and arrangements produced by man, such as molten lead poured in water, casting of lots, etc. Dreams here mean those expressly prepared and prayed for with hope of intercourse with gods or the dead. Portents or prodigies are unusual and marvellous sights coming from the lower world. Here we are considering artificial divination.
The above article is from http://www.newadvent.org/cathen/05048b.htm
I started this post with the above article to provide some insight as to how many Christians see divination. Obviously as Pagans we know that what we get from divination does not come from "evil spirits" but are simple messages from the universe that tell us how things are or will be if we continue on our current paths. There is no evil behind it at all. It is simply used as a guide to help us. I am going to attempt to give a little insight into my thoughts on the topic of divination, specifically Tarot.
When it comes to Divination, there are more forms than most normal people could count. It seems like everyone has their favorite form. Mine happens to be Tarot. I have tried others like runes, but just cant seem to make any sense of the symbols. While I have not given up, I still remain loyal to tarot. There is just something about how each card forms a piece of the overall story of the reading. No matter what deck you pick up, you can usually get a sense for what the cards are telling you just based on overall basic knowledge.
When it comes to actually using decks there seem to be at least two schools of thought. One says that you find a deck that works for you and stick with it. One the other hand there is the thought that is does not matter how many decks you use, as long as they speak to you. I am a member of the latter school of thought. I currently have two decks that I use. The ones that I use are the Transparent Tarot and The Quest Tarot. Both of these have AMAZING artwork, and really speak to me when I do a reading. I also personally feel that it is important to have other decks available for reference. One that I have found particularly helpful is the Tarot of the New Vision.
You can easily open and Pagan/ Wiccan/ New-Age themed book, and each of them will swear by one or another form of divination. What is ultimately important in the end, is to make sure that you are able to work with your chosen medium. It will serve you no good if you are not able to connect with what you are using. Also, keep in mind, that no where does it way that as a Pagan you need to be able to do divination.
If you should decide to pursue divination keep in mind that it does take practice. If you go into it thinking that you will pick it up right away without studying, it will be that much harder for you to connect. Don't be afraid to ask for help and guidance. Above all things, divination should be a way to connect with yourself. If you don't know yourself on a deep level, it will show when you go to do readings.