I have. I view them as a I do anything else, as a "spiritual" tool. The whole idea of the Tarot is that either you or somone else uses the subconscious mind to pick the cards pertaining to your inner thoughts at the time.
You can use it as a tool or entertainment. Trust me, Satan "ain't" going to rise from hell and come and get you. The only thing you shouold be scared of when it comes to anything of the occult is yourself and your innermost thoughts. Just like the Ouija, you're not conjuring up spirits that are not already there for whatever reason. You are rather just communicting with them in a way that you can understand and possibly they can understand you. Or... you are just communicating with your own subconscious or even deeper levels of consciousness. As for differing decks and layouts, it doesn't really matter, the cards are cards. No more special than a rock you can stare at and gain insight but with cards and such you see the insight of someone else.
A big warning though. Before delving into the "occult" whether it be investigating the paranormal, Tarot cards, Ouija or anything else, learn about it first. Learn how it is supposed to work and the theories of the dynamics of consciousness. Your own consciousness my let you see glimpses of yourself that you are not comfortable with and this will pose a whole different set problems. Chances are that if you are afraid of things that go bump in the night, don't delve into the "occult".
A lot of people see themselves one way, not in just in terms of gender, and when other possiblities of different realities are brought to them the whole world comes crashing in on them. Depending upon the person this is a blessing or a curse. I'm not knocking any religion but will use Christianity as an example since everyone is familiar with it but no way limited to just this one religion. You spend your whole life praying to God and trying to keep Satan at bay. That Jesus was the only Son of God and he will help you with all of your problems if you just ask. That you will go to heaven and reside with the Lord in eternal bliss after you die. You hold these beliefs near and dear to your heart. The perception of yourself identifies with these beliefs and because of the human ego you become one in the same. Then one day, BAM! A door is blown off of its hinges and you are shown a totally different aspect of reality. It can be devistating to the Psyche.
Another warning. If you have any beliefs that are set in stone and identify with those beliefs to the point that they are a part of you and how you see yourself but want to delve into matters of consciousness, open the door slowly and let the Psyche have small glimpses and get use to it. Don't set your beliefs as this or that but what can possibly be. Remember the Christian, but not limited to Christianity, saying that so many forget "With God, all things are possible". Not just limited to the five senses and perceptions.
