A superb online resource which has valuable content laid out in sequential articles that can help us all become better writers is here: http://outstandingwriter.com/
I have read and enjoyed these posts on Corey's blog and all of them had great, timeless information.
* How to Develop a Personal Tone in Writing
* 25 Reasons Your Writing Sucks
* 10 Things to Do Before Writing Anything
* How to Build a Better Blog with Sequential Posts
* 30 Post Ideas for Writing Pillar Articles