Of course getting "free" search engine traffic is the best kind of free advertising, but your site probably has to outrank most other competitors to get a productive search ranking. After doing the small on site optimization and incorporating important keywords in content, the main work in SEO is getting decent links from other sites, junky spam links you can buy for less than a penny each may cause more harm than good in the long run, to not raise suspicion a new site just needs to add a couple of links a day max, mixing the relevant sources, some of these links bring in direct visitors as well. SEO is a relatively slow process, it's worth getting some guides.

You probably want to have a presence on perhaps a half dozen social sites like Facebook and Pinterest, as well as Youtube these can both make you look like a much bigger player as well as improving your search ranking. It's hard to sell without being a salesman, establishing relationships with prospects on these social sites may be worth the creative effort.

Here's a Google guide mainly discussing on site SEO.

http://www.google.com/webmasters/docs/se...

Some believe that relying on the whims of search engine ranking algorithms that can "erase you from the map" after one of the regular revisions.

http://www.seomoz.org/google-algorithm-c...

The alternative, paid advertising has the advantage of being scalable, you can get 10x the traffic overnight by just raising your ad spend. It's not uncommon for a successful web business to have not made money at the beginning, Facebook went something like 6 years in the red. After initial testing and refinement of a campaign's text copy, keyword selection and landing page design paid ads might begin to be profitable and scalable. In some cases the advertising companies become a store's biggest partner, costing more than inventory in some cases.



Those with an operating budget may test their store site at the start using paid traffic that's too expensive to be profitable (Google's Adwords ads with the right keywords provides some of the most qualified prospects) if they get no sales after getting 200 or so of these strong prospects they may redesign the sales funnel or abandon the site and product concept. Someone using free traffic sources may not discover for some time whether their site works.

The big store site players recognize that securing new customers is the most important goal, often advertising and special discounts can make the first sale unprofitable, but they understand that it's a world easier to make additional sales to a proven buyer, maintaining a relationship with customers through periodic emails is an important part of a long term revenue plan.

Those annoying ad-retargeting campaigns that became popular in the last year or so have proven to be quite effective by persistently inviting back prospects that have merely demonstrated an interest in visiting the site.

The blog on this seo authority site has some valuable information, particularly their Whiteboard Fridays videos, though much is highly technical and only meaningful to large enterprise sites, they have compiled a nice list of marketing resources.

http://www.seomoz.org/dp/the-internet-ma...

As far as I know PTC websites are the best way to advertise digital goods. PTC websites are those where advertisers advertise their product and members get paid for watching advertisement. And we all know that when someone get money to do anything, he/she does it seriously. So it increases that chance that you will get quality and targeted audience for your product. Also if your digital product is something about earning money online, advertising on a PTC website increases you chances very high because members of PTC website are the people who are interested in making money online. Even Click bank also recommends advertising on PTC websites.

I am also an affiliate and successfully using this strategy. I recommend you http://www.adrabux.com to advertise.This is a very good PTC site with very low advertising packages. Image showing their advertising rates is attached below. May be their rates have been changed now but they are value for money.