Here’s a site full of interesting noises: freesound. You can search for anything, and it will return Creative Commons licensed sound samples; if you want the sound of a phone ringing, or wind chimes, or throatsinging, or thunderstorms, or someone being tortured, or a good laser death ray, there it is. I started looking for more organic things, like whale songs, crickets chirping, frogs croaking, bird songs, etc., and it’s amazing—all kinds of stuff turns up.
One creepy thing, though, if you have squeaky mattress. You’ll also discover that people are recording what their neighbors are doing late at night.
It’s very addictive. Now I have to get back to work on composing that genetics exam…