"A proposal essay is simply a statement in writing that serves the purpose of attempting to convince a reader that a product, project or investment is a good idea."
Other Helpful Links
For help with writing a proposal essay see The Composition of Everyday Life (Metz), Chapter 11, pp. 350-381. See link here.
Another great resourse can be found online at the Hub Pages website. This user-friendly website includes the important sections of a proposal essay and includes and example of a typical paper from start to finish. See link here.