I have never lost a pet myself but I had a friend who lost both kittens who wandered off. She put up flyers and posted to a local email list. No results from that. One cat returned on its own one day and then about a week later I was going to see her and the second cat came meowing up the steps so I was able to walk in the door carrying the truant in my arms!
That was a sweet moment.
Unfortunately my friend continued to be rather lax in keeping her cats from wandering and they both wandered off again and were not recovered. Made me sad. I wish I could have adopted them! but at the time I was not free to do that.