Need articles written

Looking for someone to write articles for us. 500 word articles mostly. You would agree to the terms that by submitting to us your article, you would surrender the rights to the article and it would not be placed in any other website, blog, or to another client etc. We need someone able to turn the articles around within 48 hours each article. We want to do a test of 15 articles. If the test works out we would love to extend the relationship and would be willing to pay daily or weekly for articles done by you.