Mike,
Sorry I didn't get back to you.
I believe you stated that
Objectivism can be summed up as "capitalism = good" . While that's one of the end results, Objectivism starts by defining individual rights, the nature of man and reason, and the ethics of rational self interest. When you extend her philosophy to other aspects of human existence, the political-economic corollary is laissez faire capitalism.
The single best introduction to Objectivism is a book written by Leonard Peikoff, the heir to her estate. The title is "Objectivism: the Philosophy of Ayn Rand". It's available on Amazon. Peikoff has written several excellent books, but that's a good place to start.
Another interesting one is "The Ayn Rand Lexicon: Objectivism from A to Z" by Harry Binswanger. The tone is a little more light-hearted, but equally informative.
I'm a big supporter in many of her ideas, though some of her actions (and actions of her followers) were often inconsistent with what they were promoting. I've also seen Leonard Peikoff on different TV 'debate' shows, and he's had considerable difficulty debating against other points of view.
Kevin