TypoWiki. From the people at Typophile. TypoWiki is a wiki containing all manner of typography-related information -- history, terminology, and more. If you want to read about the Roman contribution to engraving, or about Gutenberg's invention of letterpress printing, this is a good place to start.
i love typography. A typography blog, and another good resource for definitions, pointers to good and useful font families, and more. There's also a lot here about developing new fonts, in case you're thinking of a career change, or at least acquiring a new hobby.
set in style. A blog aimed at the attorney audience, with tips on writing, publishing, and typography. The emphasis is on writing technique and common errors, and there's even help for those trying to create firm-marketing materials.
Microsoft ClearType. This one relates not to the printed page, but rather to Microsoft's technology for improving the display of onscreen type on LCD monitors. Those running Windows Vista should have the feature enabled by default, and XP users can see this FAQ for instructions to turning ClearType on. Most people will find that they much prefer the clearer, smoother type produced by ClearType.