I had read a classified ad by an author who wanted to hire a research assistant on the Internet. I was familiar with the author's books so I wrote a "Book Review" of his most recent title and emailed it to him.
The ad was three-weeks-old by the time I had read it so I had to work fast; reading the book and writing the review took two days.Amazon Offers SUPER SAVER SHIPPING!
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After a couple of months went by he was kind enough to reply to my email. He had received 350 replies to his ad! which had run in one of the major metro areas.
So you can see that responding to classified ads for writers or articles by writing something specificly for that magazine or website may be a good exhibition of your writing skills but not get your article published.
Writers Digest Handbook Of Magazine Article Writing Edited by Michelle Ruberg covers finding the right magazine for your work.
Another ad I responded to by emailing three articles I had already written and had published. This was for an automotive "Blog" that was going to be published on a regular schedule. Automotive articles take a lot of research and fact checking so I can see why they advertise for articles. I never heard back from him so I think people get an idea, run an ad to see if they can get somebody else to do the work for them and then decide whether to proceed or not. Writers Digest handbook has an article on creating articles established magazine editors are looking for and how to contact them
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