No luck yet?
Is he normally an indoor cat? They often don't go far--try putting out an old shirt of yours and the litter box by the back door. Look under porches or in sheds where he might have gotten shut in or is hiding. Make sure you notify all the shelters and vets in the area and give them posters--also check the shelters in person since so many cats are taken in that the staff may not be able to recognize Poo easily.
Also, if you can post the pics of Poo right in this thread instead of in a profile album, it would be a good idea. A non-member looking for a posting about a lost cat in your area might do a search and find this thread--but unless they join up, they can't access your profile or your albums, so they won't be able to see the pics.
Good luck, mamma41. I hope you're reunited with Poo soon!