Casting actors for RPG characters

This is a cool little trick I'm looking forward to using a lot more: using the vast supplies of nice, clear actor headshots out there as an easy (and, often, immediately evocative) way to illustrate what an RPG character looks like. In the Spirit of the Century campaign I'm running, we've got player characters who look like Lance Henriksen and David Tennant (among other people). Also, there are NPCs who look like Christopher Walken and Bob Hoskins. Now, we've also got characters who use historical figures or total unknowns for their portraits, but using people we've all seen in movies and television is especially cool for this reason: It doesn't just show you what the character looks like, but also suggests a lot about how they act and talk.

Now, credit where credit is due: I think I might've read about this idea in an actual play write-up of a game called Geiger Counter before I actually tried it in my game. (I'm not really sure about the chronology.) This is a really interesting-looking little game--still under construction, apparently--by a dude named Jonathan Walton. It's intended to simulate the sort of sci-fi and horror movies where some monster (or monsters) inexorably kill off most of the cast, until the final survivor (or survivors) defeats or escapes them at last. (So, you dig how utterly brilliant the title is, referencing not only radiation, but H.R. Geiger's Alien designs, and the character-by-character countdown of such films?)

So, ever since reading that AP post, I've been thinking about how a great big pile of head shots of reasonably well-known actors (especially character actors!) would be a goddamned awesome gaming tool, utterly perfect for making up new characters on the fly. It'd be an especially good fit for modern-ish games with a cinematic tone, but I don't think it'd cause too much cognitive dissonance if I told my group that a mercenary captain in some Dungeons & Dragons encounter is being played by Brian Thompson. (And I'd definitely want to have a photo on hand, of course, so that I don't have to tell them "You know, the alien bounty hunter guy from The X-Files.")

So now I'm just wondering if there's somewhere I can go to just download huge, retarded piles of Hollywood head shots. Google has not been too helpful, so far. Failing the discovery of a single source, I guess I'll just start putting together a great big list of appropriate names (perhaps assisted by Fametracker's awesome Hey! It's That Guy! section) and start hitting Google Image Search.