It takes anywhere from ten minutes to a half hour to write the Victim -- usually because I already have an idea in my head before I start writing. There's nothing technically exciting about how I write the victim ("Remember kids: always hit the 'enter' key at the end of every paragraph") so instead I'll talk more generally about the kind of stuff people ask me in regards to the column.
Where Do You Get Your Ideas?
One of the first places I check is our mailbag where people are welcome to send in ideas. Occasionally I'll see one that'll get me going, like when someone told me the story about the Naked Guy. In at least one case, the dude practically wrote up the victim himself -- as was the case with the Tribes Hand.
But for the most part ideas just come from observing stuff around you. The reason I started the feature is because the gaming community is just so frickin' funny to begin with. Who hasn't run across some jerk in the Diablo forums or the guys secretly running a server against campus policy? Real people can be really funny, you just have to spot 'em.
Most of the ideas come from stuff that happens to me. Yes, there really is a Matrix action figure sitting on my monitor. He does make me feel badass. One time I had a terrible cold, and a victim was the result.

So I had some vague idea of a freezing guy for a Victim. In order to get things focused on gaming, I had the frozen guy's game performance suffer. It occurred to me that having some guy whine about an air conditioner wasn't funny, which is why I threw in another character named Crenshaw, who was doing it on purpose -- now, the fact that someone ELSE is turning on the air conditioner just to win at Quake, now that was funny. Most of my ideas come from real life, then I tweak them around until they strike me as plausible, but ridiculous. :)
Next: Getting Weird...