Four and Twenty Piebirds
Site offers piebirds also known as pie vents. Items are not featured online, request information by e-mail.
My Piebird Page
Description of pie birds and how to use them, with photographs and information about a collectors convention.
Pie Birds, America
Original, handcrafted Ceramic Piebirds by Carmack. Choose from many skillfully designed birds, or submit ideas for custom created caricatures.