Getting listed in directories is not as effective as it used to be. The only directory I would worry about these days is Yahoo (if you can afford the $299 then it still may be worth it) OR find directories just for your niche. So in your case, directories that target retail sites.
The reason I think Yahoo may be worth it is because it's $300 and Google probably assumes that you must be pretty serious if you're going to shell out that kinda cash for a directory listing. Plus the Yahoo directory is still pretty reputable. However if you don't have the cash then don't worry about it.
It's not an absolute necessity to get traffic.
The reason why directory submissions became popular is because Google looks to see how many other sites are linking to you (backlinks). But since more and more "instant directories" started springing up everywhere and people started submitting to every directory under the sun, Google started devaluing these listings.
So going on a mad hunt and doing exchanges for all these different directories is just not that beneficial anymore.... especially the ones that want you to put a link on their site in return.
I don't do directory submissions anymore but if I did I'd only look for the ones that offer a one-way link. In other words, no exchange. You put a link on their site only (
www.dmoz.org for example). These are harder to find these days, however.
It's really getting to the point that the best quality links are one-way links from other Webmasters who are referring you within an article (not a "Sponsors" or "List-o-Links" page).