A friend, Don M.F.H., is exploring self-publishing for his book as a means to potentially getting a traditional publisher down the road. He wrote about his ideas on his website, asking me for input.
Truthfully, I have limited direct knowledge, just what I've picked up by osmosis and over the Internet. But I did some poking around for him, and wrote a reply that was probably way too long. (I think my response was longer than his original post.) If you're curious, check out So I had this idea ... on his blog Driving to Oahu.