Ryan, I think they're asking for more info about my comment.
Ryan's right different books do different things; of the ones I have at my fingertips when I'm working on UX Design, Beaird's is important because it gives a 10,000 foot view of graphic design. For someone in my position who didn't have the artistic training in college, that's what makes Beaird's book so important to me. He covers design processes and tools which is not how most art books are organized, and it's why the book makes an unusual amount of sense to me as someone who previously focused mainly on making form follow function. I now use a modified version of Beaird's model: 1. XHTML prototype with no CSS, 2. CSS Positioning (these two correspond to Beaird beginning with Layout) 3. Color (a. Choose a color scheme, b. paint the design with it) 4. Texture (add 3D feel to the page) 5. Typography and font styling 6. Finalizing imagery And while I've adapted his model to work for me, I will frequently find myself referring back to it for details about executing each step.
The book that's most important to me personally is the one I mentioned earlier, Zen of CSS Design, by Dave Shea. Beaird discusses best practices in the web design process. Shea discusses and illustrates with examples how to construct stylesheets in CSS. There are other books, but none that cover best practices in CSS so well. There are more recent books and some cover new ground, but there's very little that supercedes what's written in Zen they just cover new areas. And most of the books that are out there about working in CSS actually have a lot of "errors", ie they tell you to use a technique which will technically work for the example they provide, but don't work well in general and are not a best practice. Cedarholm is one of the best out there, but I've even found problems like this is his books (both the classic and the new one). Sitepoint books are almost unique because they are so well put together and recommend solid design principles (chalk this up to the reliance on sound fundamentals and web standards). However, I've found no other book that works so well as a reference for production quality web design and is so comprehensive about how you "ought" to build your CSS and why. If you don't like Shea, my alternative recommendations would be the two Sitepoint books, Ian Lloyd's Build your Own Website the Right Way, and Tommy and Paul's Ultimate CSS Reference. The only other book I've really liked was Andy Clarke's Transcending CSS. It's not one I have on my shelf, but it was a very interesting read and changed my design habits. I now use "float" almost exclusively for its behavior not for positioning; I use relative and absolute positioning to get XHTML elements where I want them to go.
I also keep a couple of Leatrice Eisman's books (Pantone Guide to Color, and Color: Messages and Meanings) on hand. I don't use them much because they only relate to one phase of design, color. But that's always where I start if I get to develop the color scheme, thumbing through to begin brainstorming color chips and working them into color studies.