Another general writing community website here at Creativity Portal but this one claims to be an award winner with millions of visitors annually. It is a very comprehensive site with writing prompts, links to coaching and details on their affiliated coaches. You can also book training sessions to help you develop all manner of writing skills.
There are hundreds of articles from book reviews, tips on arts and crafts (not just fiction writing), advice on how to and how not to write and an large directory of writing prompts to combat that writers block. I particularly like the Imaginiation Generator and the photographic prompts.
My only complaint is I feel that the site looks a bit too busy. In this day and age, ease of exploration is king and this site is not particularly easy to navigate. Still, there is so much there you will undoubtedly stumble on something particularly useful.http://www.creativity-portal.com/