Tissy, if you haven't found Delilah yet, go immediately to this site:
http://missingpetpartnership.org/
They have recovery tips there and ways to find a tracker dog in your area. I have had experience with them and they helped us find a dog that was lost for over a week. That story is here:
http://www.flickr.com/photos/tigerrules/459980128/
This is the first thing I would do if my own dog got lost. Please do not waste any more time-- try to find a tracker dog in your area.