Mind Tools: "Writing Effective Emails: Making Sure Your Messages Get Read and Acted Upon"
Read this article on proper use of workplace email. This article covers creating appropriate subject lines, making your point, specifying the response you want, being a good correspondent, and using pointers for internal email. Note the good and bad examples of email writing in each category.
Click http://www.mindtools.com/CommSkll/EmailCommunication.htm link to open resource.