In addition to the many good books out there, you can get a pretty decent grasp of the investing world just by surfing around a bit. Many big sites have in-depth mini-universities. There is a lot of overlap and the some of the advice is pretty generic, but I still use them as resources whenever a question pops up. Here are a few:
CNN Money 101
Kiplinger.com Basics: Tutorials
SmartMoney University (My overall favorite)
MSN Money Decision Center
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