POD and Self-Publishing

I've had a ton of people ask me about self-publishing, and about CreateSpace in particular, since they're who I used for my grammar book.
First off, WHY self-publish? There are good reasons to and very bad reasons to. Thinking you'll be a sudden millionaire is right up there with why NOT to. (Ain't happening.)

A few generalizations about self-publishing:
-Non-fiction has a far better shot at having sales than fiction does
-Bookstores will almost never stock your book
-As a result, your chances...