Oh most of us that change it so often make the icone ourselves.
If te ever find an image te want to be an icona I could always make it for you. XD Ive made probably near a thousand o so icone da now. I really enjoy making them
But essentially te cerca up whatever te want an icona of, te find an image that te think would make a good icon, take it to some kind of editting software (or paint if te dont plan to do much to it), and at the very least, crop the image to be the size te need it to be (square)
te can get più creative with it the più your practice too
I usually used
link to modifica and crop and all cause its like Photoshop but online free and has no downloads. Not as good as Photoshop but definitely plenty enough.