How would you find her? - she's invisible.
Unless invisible people can sense other invisible people. I have often wondered about this. If you are invisible, then that means that light passes through you, including your eyes. So light doesn't have a chance to bounce back from our retinas and enable the eyeball to...well....see. Rather, light passes right through the retina. Invisible people in comics and movies seem to get aroung okay and don't appear to be blinded - but why not? In getting invisibility, do they gain some other ability to sense light and/or their surroundings? Does this allow them to see other invisible people or things? Does this secondary power function when they are not in a state of invisibility?
I have actually spent hours contemplating such things.