Sorry to hear about this Lena, sounds horrible.

I had two cats do this, one I found her sitting by the back door like a sentinel about 9 days later, the other we had to remove a ton of siding and boards to pull her out of hole in the wall. (crazy cat!).

Not much to contribute other than well wishes that you get her back safe and sound... cats seem to be a bit like snakes, the minute you are convinced that it is not going to happen, voila... kitty (or snake) appears.

*fingers crossed* for you.

Bruce