Not all pets will run, some will stay close to home, and there is a good chance you can find them quickly. Skip them entirely if you can see clearly that your pet has escaped and it is obvious that the escape occurred some time before. You want as many notices as you can make to put up around the neighborhood, and beyond. Tape them to lamposts and such near street intersections. People must be able to read them from their car, so the lettering must be large.
Paper is too flimsey.
Then put them up at the entry points to nearby neighborhoods. Remember, a large dog could easily travel 10 miles in an hour. M ake sure your pets wear a woven collar with tag at all times, even at night. Special cat collars are available that breakaway in case they get tangled. Should your cat get up a tree, you don't want the collar to get caught and strangle it.