How much do you pay to 'self-publish' your book?

I've had an interesting question come up a few times in the past several weeks. Several of my friends who are thinking about self-publishing have told me they are looking at publishers, but they all seem so expensive. 

What? The first time this happened, it took me a little bit to make sure I understood correctly...people are charging to 'help' you self-publish? Apparently that is, indeed, what is happening. So, I decided to post a blog just in case someone else out there is thinking abou...