my heart goes out to you. it is the most indescribable feeling in the world. i have experienced it myself. it is especially bad when it is in a wooded area, any breath of wind and the rustling of the trees makes it nearly impossible to hear anything else.
gee, i wish i could do something for you... my stomach hurts at the thought of what you are going through.
one of the first things i did was call the spca and tell them my budgie got outside. i asked them to let me know if someone reported finding a bird of that description and put signs up in the neighborhood and the convenience stores etc... close to our home.
i also spent alot of time walking and calling.
keets in the wild, don't travel by recognition of areas by sight. even if they did... it is tough because our tame birds have never been out to be able to see an area, let alone be able to recognize it. i was told to walk and call as much as possible and play keets calling out to each other. many times, our lost friends will holler back to "the others" and we can kinda home in on an area.
leaving the cage next to the house may work because it is the one thing it will recognize by sight. check shaded areas and lower spots. they don't like the tops of the trees, they like sheltered areas.
i did alot of bush crashing, day and night. my saviors were the spca. the person who found ozzy had called, reporting the little bird they found. she was THREE BLOCKS AWAY.
you and peace are in my thoughts and prayers. a friend told me about sending positive "vibes". they are coming your way, full force.
good luck lagirl,