The only major party presidential candidate who understands both the problem and the solution to our current economic crisis is Ron Paul. Either that or he's the only one with guts enough to talk about it. You can find Paul's analysis of the situation here.
For a really good introduction to economics in general, read Thomas Sowell's Basic Economics: A Citizen's Guide to the Economy. In fact, read anything and everything you can get your hands on by Sowell. In my opinion, he's one of the most insightful thinkers of our day. You can read his weekly column here.
Another fine introduction to economics is Henry Hazlitt's, Economics in One Lesson. It's become a classic.
Murray Rothbard's What Has the Government Done to Our Money is good at explaining how monetary policy affects the value of the dollar, especially the effect of removing the dollar off the gold standard.
For a distinctively Christian approach to these subjects, try R. C. Sproul Jr.'s Biblical Economics, and Gary North's Honest Money and Salvation Through Inflation.
Our current economic situation really is dire. Unfortunately, as Ron Paul says, just like the proposals of FDR during the Great Depression, the various popular prescriptions to address today's crisis (including President Bush's bail out plan) are only going to make matters worse...far worse, like a doctor prescribing a Super-sized Double Quarter-pounder meal to treat a patient with high-cholesterol.
The problem is systemic. That is, it's not just an isolated problem here or there. The problem goes to the very core, and affects every aspect of our economic system: unbacked fiat money; fractional reserve banking; expansion of credit; artificially low interest rates; lowering of lending standards; government-backed home mortgages; and a host of other ways the Federal Reserve manipulates the market; etc.
The president's bail-out plan is just more of the same.