Article writing (web design, internet marketing)

I need a writer for a set of 50 articles, which will cover web development topics like web design, e-commerce web design, seo, internet marketing, social marketing, php development. I will provide titles and links which have to be used in articles. English must be excellent. Articles must be between 500 and 600 words and have to pass 100% copyscape. You must be available to communicate through email. Eventually, if things go well we can build a long-term partnership. Thanks and happy bidding.