The Warner Brothers Studio lot has a special area dedicated to showing off some of the vehicles that have featured in their films. Universal Studios has one as well, but you can't get close to anything, but that's another story...
While I was there in 2007 they had the Ford Anglia from Harry Potter on display. Unfortunately the photo I took didn't come out as well as I would have liked:
Funnily enough Corgi produced a scale diecast version of it, though it doesn't have the holes in the windscreen. It also looks a lot less battered than the real one in Warner:
In common with most of the film and TV items produced by Corgi it's currently not available from them directly, but I did manage to pick one up from an eBay vendor for next to nothing.