Becoming Better at Math How can I become excellent at math? It really interests me but when I fail I become demotivated and begin to give up.

EDIT: Could anyone suggest books for someone with a math education that just barely touches on high-school Algebra (got into parabolas, rationalizing, some graphing and functions). This is what I am currently doing: attending high school as a Junior.
Be honest with yourself about what you do and don't understand. Don't fall victim to "proof by intimidation," where someone attempts to shame you into saying you understand something by implying that you're dumb if you don't. Always ask questions until you really get it. Similarly, don't let yourself move on before you understand something fully; pretty much everything will come back to bite you at some point down the line.  If this seems like a pessimistic attitude, it's not - it is simply humility, and humility is the path to genuine knowledge.

EDIT: I just noticed your question about books. How To Prove It is a great transition to more advanced mathematics.  After that, check out some of the Dover books, they are all very cheap and most are decent introductions to their respective subjects.
You may find it useful to start with http://www.khanacademy.org/

Once completed, look for additional resources and side by side track how much you completed from http://mathworld.wolfram.com/