A few of my friends are big believers in the power of positive thinking, putting things out there, asking for what you want. Well the universe heard my plea and Oscar was found! Not moments after I posted the reward notice I was struck by the idea that he must be on the couch somewhere. Instead of just looking behind the cushions I lifted the cushions right off my couch and I found him! He was under one of the very heavy bottom cushions - looking like Flat Stanley but otherwise unscathed. Thanks for your comments. I think it helped having a few people put their minds to it.
Now I need everyone to start thinking thin thoughts for me, thanks. :)