AIGA: The professional association for design.
Lynda.com: Excellent, affordable online tutorials for all sorts of software that are critical in the communications field, including web development, design, video production, etc.
Search engine optimization (SEO): Basic information from the from the masters themselves…
Color and web usability: Tips and best practices for using color in a website.
Section 508 usability standards: If you’re going to work for the government, start here. If you need cliff notes, try this, an excellent recap from the folks at NASA.
Analytics: You can begin here with some basics, then go to Google Analytics to dive into it. There’s also an Analytics plugin for WordPress.
Social media information and best practices:
Web design trends for 2010: Tips from WDL and, yet again, WDL.