According to others, it's behind the glove box (as usual).
Buying new ones is pointless unless you're really in a dusty area (or if you park your car under a Birch tree dropping seeds into the intake and then find your AC condensate is clogged and splashing water on your passenger's feet.)
Since the charcoal layer is so pathetically thin, I just pull it at each oil change and blast it off with compressed air. Failing that, wacking it on the ground works too. LOL
