You can do self publishing through a number of groups (the one I use is Lulu.com). At lulu, your book can be available for sale at no cost to you.
If you're doing a "print on demand" situation(where they create the books as they're ordered), you don't have to buy a large quantity of books, and the ones you buy are at an author's discount.
Most large chains won't stock "print on demand" books, because they can't return them if they don't sell. (If you become a best seller independantly, they may make an exception, but don't count on it).
You can, however, get your book into smaller stores (gift stores, health food stores, etc) by purchasing copies at the author's price, then 1)reselling them to the stores at a wholesale discount( they usually get 40% off); or 2) placing them on consignment (you get a bigger %, but only if they sell)
There's a lot more info about self publishing, but that gives you a basic idea. I've got two self-published books out, and I'm working on a third, which gives you an idea that this is a workable practice.
There are also other ways of tackling this. I think it'd be important to look at what is your priority : a) publishing a book; b) selling your book; c)selling your book in stores; d) making money; e) other;
What would be the best approach would be heavily influenced by what your priority is....