One of the best ways to beef up your copywriting skills in a hurry is simply to study the promotions of some of the greatest copywriters in the world, both living and dead.
And the best source I've found for old ads by long ago copywriters is Lawrence Bernstein's InfoMarketingBlog. Each post features a classic, long lost ad and some details about the famous copywriter who created it. Go there, print them out, read and study them, and most important of all, copy them out by hand or type them into your word processor. You'll be surprised at how quickly you catch on.
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