Yeah, where are they? You hardly see them on the show anymore. The last time we saw some from that line were Male and Female Nidorans in "Leading A Stray". They've become my favorite line of Pokemon. I'd really like to see a Nidoqueen on the show again. Heck, I'd like to see anyone of these Pokemon on the show again.
Also, Aggron? Again? Didn't we just see one in "Steeling Peace of Mind?"