See what I'm doing? I'm burning through A Book Apart's wonderful library. When they say "Brief books for people who make websites", they mean it. It's clear, precise writing with well organized content. Beautiful.
There's more than just CSS tricks to be found here. It's a handy resource I've consulted quite a bit. The site also serves as a beautiful example of responsive design. These guys aren't screwing around.
Here's a useful reminder for all the web designers and developers out there. The next time your client doesn't believe you, just send them this link.
I just finished reading this book and it was awesome. It's short, but don't let that fool you. This thing is packed with techniques for creating thoughtful and organized CSS.