The first thing you will need to do is to choose a language to program in. You have a lot of choices, including Basic, Pascal, C, C++, Java, etc., and there is a great deal of debate over which language is best for beginners. For a discussion of a number of popular languages, see John Hattan's excellent article, What Language Do I Use?
I'm going to recommend starting with C and C++. Some people will say that those languages are too advanced for beginners, but because I started with C++ myself, I tend to disagree. In addition, C/C++ is the most widely used language today, so you will be able to find a wealth of resources and help. It does not really matter whether you learn C or C++ first, because once you learn one, learning the other will be a trivial matter. However, if you choose to learn C++ first, make sure you understand and can use procedural programming before learning object-oriented programming (i.e. hold off on learning about classes until you can program well without them).
If you start with C/C++ and it turns out to be too difficult, there is nothing wrong with going back and learning a simpler language, such as Basic or Pascal. But I really think that if you stick with it and find the right resources, you should have no problem with C/C++.
Your next question should be, "How do I learn C/C++?" I'm glad you asked. The best way is to take a class. Having an instructor and TAs available to answer questions and help you along makes a huge difference, and the programming assignments will ensure that you actually apply what you are learning.
If taking a class is not an option for you, the next best thing is to get some good books. Don't stress too much about picking the "perfect book", because you are probably going to buy several eventually. I'd suggest going to a local bookstore and spending some time browsing the introductory C and C++ books until you find one that you understand and think you can learn from. In time, you will want to pick up some more advanced books, and probably a reference, but once you have some knowledge of the language, you will have a better idea of what you need. See our books section for some suggestions.
At this point, I want to take a moment and address something that I have seen as a concern for a lot of beginning programmers, especially younger ones: not having money to buy books and other things. First, there are free resources available, including your local library, and Macmillan Computer Publishing, which has hundreds of programming books online at
www.mcp.com/personal. But second, if you really want to become a good programmer, you have to plan on making an investment in it. Use whatever (legal ;<) means you have to come up with some cash.
There are also a number of tutorials available on the web for learning C and C++, but I have found that tutorials are better for supplementing what you learn in books than for being a stand-alone resource.