lots of what I expected in this thread: people defending their convictions.
well, seriously, you'd have to be a dumb piece of shit if you think that everyone born in the same month is going to be more or less the same as each other. Knowing only the Zodiac signs, I rejected astrology as pure BS for a long time.
About two years ago, I met a girl who was really into astrology and all that hippy stuff, and she taught me a few things about it. She told me that, for example, horoscopes pertaining only to the main Zodiac sign are pretty much useless, but that if I did an entire horoscope using the date, time, and location, then you could draw up a star map for what it looked like when I was born. Surprisingly, there were a great deal of interesting tidbits in there that did ring true.
I use tarot cards when maybe once or twice a year, when I'm feeling confused or apprehensive. I use them as a way to find out how I really feel about certain things more than I use them to predict shit. If I "ask the deck a question", pull a card, I pay more attention to my reaction regarding the card's meaning and the question than the actual meaning of the card.
I think it's another tool you can learn to find out more about yourself. But if you're looking for guidance from the stars, you're probably just grasping at straws.