You need to know your target audience and cater to them. Your target audience are your potential clients - I'm not saying do it for free, but offer deals over holidays. Let everyone you know that you do photography, get business cards too. I never generated any interest online but as soon as I told people face to face, they instantly were interested in what I had to offer. Word of mouth is your best friend but if you're not careful it can be your undoing. If you've never worked retail I suggest you do for at least six months to a year so you're use to crazy people wanting all sorts of weird requests because it will happen.
If you're serious about this, it's a good idea to start a blog, post tutorials, perhaps write a book. It seems like most of the modern photographers I know about, spread the word that way.
If you can afford to, and are willing to take the risk, you might consider giving away some of your images for use in memes and such. It's a business decision how you license the images, but it's something to consider.