["Designing with Web Standards"][1] covers HTML, CSS, and light JS, but importantly hammers home the concepts of progressive enhancement, graded browser support, and working around browser quirks in a sustainable manner
["CSS Mastery"][2] is a foundational text, as far as I'm concerned, covering a combination of common techniques and as well as covering the browser rendering model brilliantly
On the JS Side, ["DOM Scripting"][3] was fantastically handy for me, as it covers the DOM event model, modifying the DOM in place, and the proper way of building