• Sarah's HTML Cheatsheet
• Special Characters in HTML
• Hex Code Color Charts
• Validate your HTML
• HTML 5 Overview

• CSSplay - Prime examples of CSS
• Mashable's Facebook Marketing Tips
• W3C - CSS Tutorials
• Soh Tanaka - Incredible designer that will help you think and style outside the box

• Bring Your Forms to Life With JavaScript
• Internet.com's JavaScript Resource
• W3C - JavaScript Tutorials
• Thau's JavaScript Tutorial

• JQuery.com - Home of JQuery
• JQuery UI - A great resource for learning how to style widgets
• W3C - JQuery Tutorials
• LearningJQuery.com

• PHP.net - Home of PHP
• phpMyAdmin - MYSQL admin tool
• HotScripts.com - A great resource for developed PHP scripts
• W3C - PHP Tutorials

• Art and the Zen of Web Sites
• Complete Guide to Pre-Installed Fonts in Linux, Mac, and Windows | A Padded Cell
• Pantone Colors, Pantone Color Guide, Pantone Uncoated Stock - PMS - Materials-World.com
• Web Pages That Suck.com -- Examples of Bad Web Design

• SEOmoz - The beginner's checklist for learning seo
• SEOBook - Renown SEO experts Aaron Wall (aka SEO God in Sarah's world) and Andy Hagans
• SEO Basics - by Aaron Wall
• SEO Training Courses and Custom SEO Training Classes

• Ultimate Guide to Twitter Marketing
• Mashable's Facebook Marketing Tips
• SEOMoz's Facebook Marketing Ultimate Guide
• Effective Marketing on LinkedIn

Timeless

• Archived Hubspot Webinars
• Archived ExactTarget Webinars