Dynamic Drive CSS Library

Glish.com

CSS Template Fluidity

Vast links to CSS resource

Position Is Everything
Many articles on CSS, layout, and cross-browser compatibility bugs and issues.

More Eric Myers
Companion website to his book of the same name. Sample code.

Eric Myers on CSS
His earlier book.

Inspiration

CSSElite

CSS Zen Garden
Showcase of what can be done using CSS. It is an design exercise where you can submit your own entry.

CSSBeauty.com

CSS Vault