It can be very frustrating trying to get a print-on-demand book stocked in stores. There are many things you can do. You can go around local stores and ask them to stock it, you can provide copies on consignment. In general, this is going to be an uphill battle because most POD books are not returnable and are not sufficiently discounted. For this reason POD books tend to sell most of their copies online or at special events. But, at this time, local branches of many large chains will still stock self-PODs, host book signings and support local self-published and small press authors. It helps to be a regular in the store and be honest with the staff you speak to--they probably know self-POD when they see it so there is no point trying to sell them any snake oil. You can further increase your chances by donating some proportion of the proceeds to a local charity and find other ways to make your work of interest to your local community.
Some very "cunning" schemes are always circulating about how to get your POD book stocked without going to all this trouble. One is to have people special order copies. This is not necessarily a bad idea, if they are real people who really want to buy a copy. There is always a chance that the store may decide to get in an extra copy to shelve--especially if they get several such requests and you are a local author. However, this suggestion sometimes goes a step further... advising authors to pretend they want a copy of the book even though they have no intention of going back to get it. As the book is not returnable the store then needs to shelve the copy in the hope of selling it. But don't think they will be happy about it.
As a result of this type of behavior is that most stores now require a name and credit card number for special orders. Which still does not seem to have stopped a certain "Michael Evers" from special ordering the anthology 'Short Cut' from small POD press Author Identity. The credit card number, along with the name, was fake. It is unclear just how many fake orders were placed for this book but its sales number are suspiciously high for an anthology from an unknown POD press--and it is flagged "do not order" at Borders. At the current time book stores do not have a system for centrally recording scam orders, but expect this to change very soon. And at that point entire presses will be black-listed for illegal behavior of this type.
This is not book promotion, it is fraud. And what is more it is fraud that pulls the struggling POD publishing area further into disrepute. The perpetrator is in all likelihood one Kevin A. Fabiano (see the link above for the evidence), as he both owns the publisher and has a story in the anthology. Mr Fabiano essentially self-publishing in that the bulk of the rest of the book's content consists of public domain material (stories by long dead authors that can be used for free). His tactics put one more nail in the coffin of brick-and-mortar retail sales for self-POD books.