mav, here's what the Word Detective has to say--but before I get to that, I'll post this link you may want to put in your Favorites or Bookmarks: http://www.ipl.org/ref/QUE/PF/etymology.html
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Necking in the woods.
Dear Word Detective: As I flip from channel to channel, I hear a great number of weathermen use the term "in that neck of the woods." I was not aware woods had necks. What else do they have? Where does "neck of the woods" come from? -- F.W. Headley, via the internet.
Ah, the woods have many things, my friend. Ears, for instance. Actually, I may be thinking of walls having ears. But I'm sure the woods do too, and you never know what sneaky little woodchuck or disgruntled deer is out there taking notes while you're stumbling through the undergrowth absent-mindedly mumbling about your more debatable tax deductions. I had an uncle once who landed in the hoosegow on the word of a skunk who sang like a canary.
"Neck of the woods," meaning a certain region or neighborhood, is one of those phrases we hear so often that we never consider how fundamentally weird they are. In the case of "neck," we have one of a number of terms invented by the colonists in Early America to describe the geographical features of their new home. There was, apparently, a conscious attempt made to depart from the style of place names used in England for thousands of years in favor of new "American" names. So in place of "moor," "heath," "dell," "fen" and other such Old World terms, the colonists came up with "branch," "fork," "hollow," "gap," "flat" and other descriptive terms used both as simple nouns ("We're heading down to the hollow") and parts of proper place names ("Jones Hollow").
"Neck" had been used in English since around 1555 to describe a narrow strip of land, usually surrounded by water, based on its resemblance to the neck of an animal. But the Americans were the first to apply "neck" to a narrow stand of woods or, more importantly, to a settlement located in a particular part of the woods. In a country then largely covered by forests, your "neck of the woods" was your home, the first American neighborhood.