1. Create the best content you can with the best products you can possibly offer. Your content is your best advertisement - if visitors love your content, then they will go back and spread the word to others.
2. Make it easy for users to recommend your site. Viral marketing is very important -- and easy to tap on the Web. But give your users the tools. Get a Recommend this Site script from websites such as cgiscripts.com and similar directories of scripts. Some even go as far as giving incentives to those who recommend the site to their friends. If only 10 people go to your site, but these 10 people invite 10 more - that's additional traffic that you get for FREE!
3. Rank well in the search engines (organic search results, not the pay per click). Search engines can be a big source of traffic. The key is to create the best content in your niche. If you have good content, other websites will gladly link to you and offer your site as a resource to their audience. Check the on-page factors and be sure to get linked from authority sites in your topic area.
4. Send out press releases. While some sites charge hundreds of dollars per release, there are free press release submission places on the Web. Press releases allow you to (a) attract media attention; (b) get more back links to your website without sending each website an email request; and (c) get more visibility especially if your press release gets in Google News or Yahoo News. My website (see my profile) accepts free press release submission (no strings attached!)
5. Submit articles. Write articles and submit them to websites accepting author submissions. You get exposure for your business; establishes you as an authority in your field, and allows you to get backlinks for your website. If 50 websites publish your article and it contains a link back to your website, then you easily get 50 links from a single article. The more links you have, the greater your chances for increasing your search engine rankings.
6. Post your URL on free ad sites like Adlandpro or Adpost. You can also use “community” sites like Craigslist and the like.
7. If your blog is specific about a topic, for example “Joe’s Cooking Blog” or “Joe’s Fishing Blog”, you could join some Yahoo clubs with the same general subject. Then post on a regular basis and include a URL to your blog. Most clubs are OK with this, but others might call it spam. Read the rules of each club before joining and posting.