There are lots of way to get advertisement of your site.If youe site is related E commerce or any portal then you can start PPC campaign or some paid activity or your site is about products or services related then organic seo is best.
For particular times PPC is the best.For long term organic seo is best.It depends on your product and budget.
Free Traffic Methods SEO Article Marketing Video Maketing Social Media (twitter, facebook) Your List Paid Methods Banner Ads Text Ads Newsletter Ads PPC (youtube, facebook) you are getting a good amount of traffic now. hopefully you are building your list. if not you should look to add a tool called PopUp Domination. it will help you build your list
More advertising and visitibility of the site on the net is more important. you adopt any method which suits you well and you can afford too.