Hi, I'm new but I work in a bird shop and can give you the correct pronunciations!
Poicephalus is pronounced Poy-SEFF-a-luss
Caique is pronounced- Kye-eeek though there is some confusion with this one. Some people say cake and some say it as if it rhymes with pike.
Psittacidae is pronounced sit-UH-suh-dee as far as I know (it doesn't come up in conversation much)
This site says it sit uh chee dee
http://www.answers.com/topic/psittacidae-1Meyers is MY-ers
I think I got them all... so, sorry my first post is all know it all! I really don't know it all which is why I joined.