Here are some sites and pages that may be of interest.
If you haven't seen HarperCollins' C.S. Lewis blog, follow the link here.
There's a very good article here about The Elements of Style, which is often recommended to beginning writers, and which, unfortunately, is the sole link that some writers and editors have with the complex world of grammar. In critique groups I've often come across writers who can't seem to grasp what the passive voice is, and why it is often needed. This article is a good introduction for those interested.
Duotrope's Digest is one of the best guides to the market on the web. Follow the link here to visit the site.