Thank you to those of you who posted and those who PM'd me. My sister has just called me and told me that the dog was safe and sound at the Humane Society. I guess he was picked up on Route 25 and brought over there. Something tells me that the fact that my sister just had a baby boy a few weeks ago had to attribute to the wandering pooch. Golden Retrievers are usually a loyal bunch, although not immune to wandering off, as my Golden used to do so frequently.
Thanks again to the friendly folks on the forum!