One of the questions I get asked most frequently is "How do I get my book into stores?" The answer varies, depending on if you're going to the big-box corporate stores, or to individual, direct-market Local Comics Stores.
First, a few words about the difference between the Direct Market (Comics Stores) and Non-Direct Market (Bookstores). Direct Market means that your books go directly to the stores and don't come back. The comics store owners buy your books, and if they can't sell them, the store owners can't send it back to the distributor; they're stuck with them. This is why so many Comic Stores have the ubiquitous "Quarter bin" -- it's to move stock that they can't sell at full price. They have to sell any overage at a loss.
Non-Direct Markets, on the other hand -- usually big-box stores like Borders or Barnes and Noble -- have the option of returning books that don't sell after a specified amount of time. In the world of fiction, they don't even bother sending back the entire book. They rip off the front cover, put the stack of covers in an envelope, and mail it back to the publisher with an invoice asking for their money back. The books are sold, sans covers, as remainders. Fortunately for us small-pressers, when it comes to graphic novels, most major retailers are kind enough to send back the whole book, intact, to be resold to another vendor.
Returns are one reason to be careful with your cashflow. Sure, a big retailer may place a thousand-unit order for your latest book (Woohoo!) but there's always the chance that some -- or most -- of them may not sell. Be careful what you do with that big fat check -- make sure you have enough money to refund any unsold copies. How do you know how many will be returned? You don't. You pray that they all sell. They may not all get returned at once -- they may come back in dribs and drabs. In all reality, you probably won't have to write a check back to your distributor for the returned copies. What's more likely to happen -- it happens to me all the time -- is that your distributor (in my case, Diamond) will keep a running tally of how much money they're sending back to retailers, and will not send you a profit check until you've earned enough to pay off the debt. So even if you don't have to write a check, you're still looking at interrupted cash flow, which can be just as bad in some cases. Some publishers have gone under from having to refund money on massive returns -- don't let it happen to you.
Of course, the easiest way to reach all of these retailers is to just become exclusive with Diamond as a Diamond Book Distributor. Visit Diamond's web site for more info on this program.
Diamond will wholesale to all of these places, and many more, including big book suppliers like Baker and Taylor and Ingram Book Group.
For Local Comics Stores and smaller retailers, there're few people more active than James Sime of Isotope Comics in San Francisco. You can chat the guy up in his message board, or read his very useful Comic Pimp column at Comic Book Resources.
For getting the actual names and addresses of all the retailers in North America, there's no better place than The Master List, a website containing the address and contact info for darn near every comic store in the world.
If there's one single bit of advice I can give you, it's DO! NOT! EVER! just copy down every store's email on The Master List and send them a spam email about your book and how great it is. Your book may be great -- it may even be a critical success -- but I tried this tactic, and it came back to haunt me. Some store owners are very particular about receiving spam emails, spam mail, and any unsolicited information in general. Trust me on this.
Read this wonderful page of information BEFORE you send out ANY emails. P-E-R-I-O-D, as Mr. Eisner would say. Then definitely sign up for The Master List's COIN program, and receive a database of stores that have officially given subscribers to the COIN list permission to send comics-related emails or mass mailings. I did, and it served me well.
Lastly -- talk to the owner of your Local Comics Store. Ask them what they like to see, how they like to be approached. Treat store owners like people, not like a demographic. Nobody likes feeling like they're the target of a marketing campaign, and everyone hates junk mail in every form, be it telemarketers calling you at dinnertime, fliers under your windshield wipers, or spam email. Talk to store owners as fellow comics readers, entrepreneurs and -- most importantly, your sales force. In many ways, your actual customers are not the readers themselves, but the store owners. They buy your product in bulk and display it to their customers. Loyal, kind and devoted store owners will go out of their way to recommend a book they like to their regulars, and some have even been known to drop a new book into a regular's pull for free, because they know they'll like it. These kind store owners, these people that love comics as much as you (hopefully) do, these people are the ones who deserve your utmost respect and generosity. Treat them well, as you would like to be treated.