One of Literarium's features is a directory of services, and cover artists are a perfect example of a service that is a high priority for modern self-publishing authors. Derek Canyon wrote an interesting post about how he designs his ebook covers. Although he uses a professional artist, he still has to make compositional decisions about the various elements, title, author, etc. Derek makes some interesting points about his approach to trying to stand out in a crowded field, and I thought it was a worthwhile read.
Derek regularly posts interesting information about his journey into self-publishing, so keep an eye on his blog or twitter feed.
Have you had any insights in designing your own covers?