In all honesty, the Vadrigar model is not all that great. Although I can understand your curiousity. I wanted to see the model myself so I wound up renting Q3 for the PS2 and trying it. I'm very glad I did. I normally avoid FPS games on the PS2. I also much rather prefer the DC version of Q3 to the PS2 version but the game modes and leveling system featured in the PS2 version are excellent. I was also really shocked at how well I played on this version. Anywho, back to the point, try to picture Uriel but without his hood, a face similar in shape to Klesk's, more lithe (sp?), a big ass sword in one hand, and a nice set of demonic looking wings. I believe he/she/it? also had the same type of flaming shader effect strewn throughout his/her/its? body that Gorre has in his er... faceplate. The scary part about Vadrigar was that he/she/it? had the same voice as the regular Q3 announcer. Rather strange and not all that intimidating though the boss fight was rather challenging.
I also must agree with Pho about how people envision the Vadrigar differently. For example, I'm pretty sure in the story (of sorts,) in the PC Q3 manual, it specifies that the Vadrigar are an entire race of people not just one person. To me, the Vadrigar would look either like Klesk or just your generic shadowy character with a black cloak and red eyes; maybe even throw in some head tendrils. The better question to ask is what the hell would Quake look like? Maybe he'd be a floating skull with wings. Maybe he'd look like a monster with a strong Lovecraft affinity. Maybe he'd just be some pale, bald guy, with a painful-looking Q carved into his head. Maybe I should stop trying and just wait and see if Raven sheds any light on this
Btw, if I do get the PS2 version and someone makes a good PS2 emulator for the PC or if I get a video card with video-in, I'll gladly take a screenshot for you.