Get a Website
When colleagues and clients (and dates, friends, etc.) search for you online, you want them to see you at your very best. As I've mentioned before, this means you need to do lots of things, like join social networks, comment intelligently on blogs, and run faster. But the number one thing to do is get a personalized website.
So how do you do that? First, you've got to get a good domain name, like lastname.com. If that's taken, try firstnamelastname.com or firstnamemiddleinitiallastname.com. I usually register sites I own through Doteasy.com because they're cheap, but unless you plan to get tons of traffic, it really doesn't matter too much.
Next, you need a site that looks good. Unless you've done it before, building even a bare-bones holding area for your resume and a blog will look crappy. So be prepared to spend anywhere from $300 to $1,000+ for a designer to build you something you really like. And don't just look up "web designer" in Google. Take a look around at people's websites you like and see if any of those designers can build you something similar. Even if they can't, you'll have some templates for another designer to work off of.
Once your site is built, make sure to keep a blog on it and update it regularly to keep the Google juice flowing! Now, to practice what I preach--