Some are free, others cost a small fee. Chances are, you'll be able to find that "perfect" font to complete your project here. Plus, lots of great tips for using fonts and font programs.

Fonts - Free
Here are dozens of freeware and shareware fonts available for Windows and Macintosh, as well as converter tools to convert fonts from one platform to the other

Fonts - For a Fee
These fee-based sites offer professional quality fonts. The most popular commercial fonts are Adobe typefaces which offer complete cross-platform compatibility between Macintosh and Windows platforms, and work seamlessly with most popular software applications. 

Font Tips
Some great tips for getting the most out of your fonts.

Font Tools & Utilities
Here are some great programs and utilities for use in managing your fonts.