Thank you all for your responses.
After quite a bit more searching,m I actually found The Nebraska Parrot Rescue in Bellevue, a suburb of Omaha. It's only about 30 miles from my home.
Having retired early, due to my wife's illness, I find myself becoming quite bored around the house, so was looking for volunteer opportunities. Volunteering at an avian rescue would not only allow me to work with and around birds, but also afford educational opportunities, as we have much to learn yet.