Here's my list, in only the loosest order. I know yours will differ, but I hope this proves helpful to someone, somewhere. I will add to it from time to time; the link will be in the "favorite posts" section of the sidebar.
The Bible: God's Word to Man. I don't think you have a snowball's chance of properly understanding the world without it.
Lex,Rex: Sooner or later, every American voter ought to read this book. It is often said that the Founding Fathers of this nation got much of their political philosophy from John Locke, and that is true to a degree, but Locke, Francis Schaeffer suggested, is basically a somewhat secularized Samuel Rutherford, Rutherford being the author of Lex, Rex. The very title of the book--while I am not claiming to speak any Latin at all--can be understood to be a revolutionary statement, as it means, I'm told, law is king, whereas prior to Lex, Rex, the prevailing political philosophy was the king is law. If you want to know why we say that the United States is a nation founded on the Bible and Christianity, you need to start with Lex, Rex.
Persecution: David Limbaugh's exploration of how America's Christian heritage and values are being actively warred against by much of the Left.
Darwin on Trial: Probably the single best volume exploring the battleship-sized holes in evolutionary thinking and evidence. Why is this important for conservativism, you ask? Simple: if you are a conservative looking for a firm base for your conception of man's rights, it helps to understand that nature alone cannot account for man's existence, and that therefore the Creator to Whom Jefferson referred in the Declaration of Independence must actually exist.
The Party of Death: Ramesh Ponnuru explores the increasing devaluation of human life, especially via abortion, in certain political circles, and explains, from a relatively secular point of view, why the subject is important to you, personally.
Slander: Yeah, I know. Ann Coulter. Yes, I would agree that over the last couple of years it seems to have become more important to her to launch some really good zingers leftward than anything else. But it wasn't always this way. While Slander has plenty of zingers, it also has plenty of research and common-sense analysis. I recommend this book as an excellent exploration of the incredible way news and history can be twisted to support a political agenda.
The Truth about Muhammad: Robert Spencer's brief exploration of Muhammad's life and why it (Muhammad's life story, that is) makes it difficult, if not impossible, to rationally sustain the idea that Islam is a religion of peace.
Basic Economics: Thomas Sowell's introduction to the subject, written largely to inform people who would vote knowledgeably. Everybody ought to know something about economics; too many people in this world think they're voting in their best economic interests when they are really voting to be eaten last.
The Tragedy of American Compassion: Marvin Olasky looks at the history of charitable work and giving in America, and explains why there is such a thing as bad charity, and why charitable governmental efforts often actually worsen the conditions they were intended to alleviate.
Invasion: Michelle Malkin explains what's happening to our borders and some of the problems caused by virtually unchecked illegal immigration.
Mexifornia: Victor Davis Hanson covers some of the same ground Michelle Malkin does in Invasion, but from a more personal point of view. Professor Hanson has lived a lot of this material.
Losing Ground: Charles Murray explains why welfare actually creates more poverty.
More Guns, Less Crime: John Lott explains the intuitively obvious: that criminals are less likely to violently assault those whom they think may be armed. Dr. Lott has committed some things that reflect poorly on his personal judgment (you can easily find them out by a little Googling), but in the main, I don't think that his material here has been invalidated. Like I said, it's pretty much intuitively obvious, anyway.
Witness: Whittaker Chambers rats out the very real Communists in the United States in the fifties. Still worth reading, because there are still very real Communists in this country today--and they may be teaching your child in the universities.
The Schaeffer Trilogy: Francis Schaeffer's first three books (The God Who is There, Escape from Reason, and He is There and He is Not Silent), published in one volume. An important step toward understanding the appalling presuppositions underlying many young peoples' worldview. Required reading in the MOTW household--and yes, acknowledging that there is a God does have important ramifications in the political world.
The Politically Incorrect Guide to Global Warming and Environmentalism: makes clear the very political agenda that is actually behind the global warming scare. Very important to your soon-to-be-voting young'un, as he will be asked to tax himself and his economy almost out of existence to stop a non-existent threat.
The FairTax Book: ditch the IRS with this revenue-neutral tax plan, grow the economy, successfully collect taxes from illegal aliens, make the United States the world's number-one tax haven for businesses--what's not to like?
The Federalist Papers: the Constitution's principal defenders explain the document to the country in the period before it was finally ratified.
The Anti-Federalist Papers: It might surprise some, but there were people who thought that even the very limited federal government outlined in the Constitution would be too powerful. As it turns out, they may well have been right.
The Politically Incorrect Guide to the Constitution: An excellent overview of why the Constitution was put together the way it was and how constitutional government has been under continuous attack since the ink was dry on the document.
The Mystery of Capital: The subtitle--"Why Capitalism Triumphs in the West and Fails Everywhere Else"--says it all. One of the most important books you will ever read.
Blacklisted by History: The real story about Joe McCarthy--that is, the plain fact of the matter is that he was right, the government under Roosevelt and Truman, and even Eisenhower, was riddled with Communist agents. The proof's all laid out for you here, and serves as a warning about how little your own government can be trusted.
Liberal Fascism: A tremendous book dwelling on the leftist nature of fascism--"Nazi" is an acronym in German, folks, "National Socialist German Workers Party"--with a great deal of history. The chapters on Woodrow Wilson and Franklin Delano Roosevelt are worth the price of the book all by themselves.
I've seen some of this stuff before, but having it all assembled in one place--well, it hits you hard what leftists would really like to see.
Reflections on the Revolution in France: After the French Revolution but before the Reign of Terror, seminal conservative Edmund Burke wrote this answer to someone asking his opinion of it all. Burke predicted the upcoming horrors of the Reign of Terror with remarkable accuracy, basing his reasoning on classic conservative principles. Timeless.
Democracy in America: Written by a Frenchman during the early nineteenth century, it's a window into what the young Republic was like during a time when the country would, by today's standards, be considered unbelievably conservative.
The Conservative Mind: by Russell Kirk. A tremendous overview of conservatism from Edmund Burke on up to the near-present. It is difficult to understand the modern conservative scene without having read this book.
Where the Right Went Wrong: by Pat Buchanan. Notes some of the differences--which are more frequent than most suppose--between the modern Republican Party's thinking and more classical conservative thinking.
The Gulag Archipelago: by Aleksandr Solzhenitsyn. If you want to know the truth about socialism--yes, I know the book was about communist Russia, but communism is merely one variety of socialism--from a first-hand perspective, this book is invaluable. Sorry. Socialism is not nice.
Stealth Jihad: by Robert Spencer. Mr. Spencer lays out the case that Islam is being deliberately advanced in the West by means of litigation and intimidation, amounting to a kind of creeping sharia.
The Politically Incorrect Guide to Western Civilization: by Anthony Eselen. A useful overview of the tremendous heritage left to us by the West.
Crunchy Cons: by Rod Dreher. I don't agree with everything in this book, to say the least, but Mr. Dreher makes some important points, especially as regards what's really important to the fundamental units of society, the family. If you've ever felt a little bit out of place with some conservatives because you bake your own bread and care more about strengthening your family than accumulating more money than you'll ever be likely to use, if you're interested in an approach to conservatism that is more than merely political, this book will intrigue you.