I got into poker for the same reason many people do
Once I got serious about poker, however, I realized that it was a much different game than I had thought it was. To play good poker, you need to read poker books, and study the game as thoroughly as possible. Instead of working on my sneer, or learning to hold my whiskey, I read a poker book every week. Instead of studying gunslinging, I studied mathematics. It turns out that poker is not a game for tough guys. Poker is a game for nerds and geniuses.
The reason that poker books are so important is that poker becomes more complicated the higher the level of play gets. Poker books will tell you about odds, when to bluff and when not to, how to bluff, and how to calculate the perfect bet to make. The first time I tried to sit down and read books about poker, I found the whole experience boring. I was in it for the action, after all, not the theory. But when I got to sit in on a game and test what I had learned, my opinion of the poker books changed for the better. Just one week of closely reading those poker books had improved my game tremendously. I skinned my poker friends alive!
No matter what your game, you should start with basic draw poker books. They will tell you all about poker hands, and how to count cards and calculate percentages. After that, you can choose your game. I like to play Texas holdem poker, so that is what I study the most. It is usually a good idea to try out a lot of different games and see what you have a natural knack for. Then you can buy a few poker books and study them. When I say study, I mean study! It will not help you to casually read your poker books. You have to dive into them deeply if you want to improve your game.