W. W. Norton
W.w. Norton & Company: Elements of the Essay: Structure
Click through an overview of how to structure an essay, including the introduction, body, and conclusion. Use the list on the right side to learn all of the elements of an essay.
Other
Kim's Korner: Patterns of Organization
Here is a run-down of several basic patterns of organization to use when writing. An example is given for each pattern, as well as an explanation.