Copywriting may be the single most valuable business skill you can possess. If you can write an effective, compelling sales letter, you can sell your product or service, regardless of what it is. Lucky for you, some of the best copywriters / marketers in history have written on the subject of writing good sales copy. There can be no definitive list of top copywriters, but what follows is my list of the top copywriters whose work you should seek to learn from.

Dan Kennedy. Dan is probably my favorite. He is a marketing genius who has a straightforward style and is very entertaining to read and listen to. He also has lots of products for sale. I am a big fan of his No B.S. line of marketing books - they're cheap and filled with powerful nuggets of marketing wisdom. His free marketing newsletter is excellent as well. www[dot]dankennedy[dot]com

Brian Keith Voiles. Brian wrote what is possibly the single best book on copywriting, "Advertising Magic". It is for sell on lots of web sites. I couldn't figure out the official web site for the book. Brian doesn't really seem to work very hard to promote it. But there are lots of places to buy Advertising Magic online if you search for it.

Claude Hopkins. In the 1920's, Hopkins wrote a book called Scientific Advertising. It is a brilliant, ageless book that boils advertising down to a set of principles that will greatly increase your chances of success. This book is available for free on many different web sites. Just search.

Jay Abraham. Possibly the most revered and expensive marketing expert in the world. Jay has a way of breaking complex marketing concepts down into easier-to-swallow chunks of information. He also has lots of products for sale at www[dot]abraham[dot]com.

Joe Vitale. Vitale is a very interesting character who is a master of many disciplines, including hypnosis, magic, and marketing. Vitale has authored numerous books, some focused on marketing, some of a more ethereal nature. But all of his writing is very enjoyable. His work most focused specifically on copywriting is probably Hypnotic Copywriting (How to Seduce and Persuade Customers with Only Your Words). You can learn more about Joe at his web site, www[dot]mrfire[dot]com.

One common piece of advice from the master copywriters is to physically write down all of the copy from successful sales letters, word-for-word. There are recurring themes that are contained in top sales letters - sort-of pieces of a mental puzzle that you need to absorb. Writing down successful copy verbatim helps lock those themes in.

The top tool in the copywriter's toolbox is the split-test, or a/b test. Run two different versions of the ad and see which one generates more business. The modern copywriter has an advantage over those in previous generations - the Internet. Pay per click marketing lets the marketer quickly test multiple versions of ad or sales letter copy. A paid search campaign has the advantage of creating almost immediate data. Whatever testing method is used, a professional copywriter knows that the only way to guarantee success is to test different versions and focus your total efforts on the version that performs the best.

There are many more fine copywriters than discussed in this article. If you look into the work of the writers mentioned above, it will set you on the road to copywriting mastery.