Yes, from what I've also seen, most hobbyist level facial recognition is done
using Roborealm or OpenCV software running on a PC, as indicated. For a
small robot/system, probably the easiest thing to do would be to get a
small Windows or Linux netbook computer. [that's actually what I plan
to do to add computer vision to my robot someday].
Another possibility is the Surveyor vision system, but that's fairly
expensive.