This list of top 10 strategies for building links is based on my own experience of building links to my sites throughout the years. It is important to keep in mind that when it comes to SEO, nothing is set in stone. SEO is a cat-and-mouse game, so I will revise this list from time to time as the field continues to evolve.

Please note that the order in which these methods are listed do not necessarily reflect their order of effectiveness. Some methods may work better than others for certain sites.

1. Submit to web directories

Submitting to web directories is a vital part of every successful link building campaign. Apart from driving traffic to your website through direct referrals, web directories provide static, one-way links to your site, boosting your link popularity and improving your rankings on the major search engines like Google and Yahoo.

It is important to note that not all directory listings are equal. Listings from trusted, established directories like Yahoo! and DMOZ are more valuable than those from the thousands of others on the net. All else being equal, a link from a directory focused on your niche is worth more than one from a general directories.

Submit to both free and paid directories. Free directories provide one-way links to your site with no strings attached, but they can take forever to review your link. Paid listings can be a good investment if the fees are reasonable and the pages on which your link will reside have decent PRs. Your sites will be listed with fewer competing links on paid directories.

2. Write articles and press releases

Submitting your article to directories is a highly effective way to build one-way links to your site. First, you write a thoughtful and informative article on an topic in your area of expertise. Then you submit it to article directories to be read by the general public and reprinted on other web sites. Appended to the end of your article is a resource box which contain links to your site and email address.

While there are hundreds or even thousands of article directories on the web, you should focus on writing a high quality article and submitting to a handful of the more popular ones. Having your article published on a top directory can be worth more than a hundred less reputable ones. If you write something that people find useful, they may pick it up and reprint it on their blogs, newsletters, etc. This is how a quality article propagates virally in cyberspace-- it virtually distributes itself without your having to manually submit to a thousand article directories.

3. Exchange links with related sites

Online forums like Digitalpoint are an excellent place to find reciprocal linking partners. Avoid sending out spammy e-mail solicitations like those generated by many SEO software programs. I get dozens of these everyday.

4. Make use of social bookmarking sites

Social bookmarking sites help bring together internet users from every corner of the world into a virtual global village. Submitting content to sites like Digg.com, YouTube.com and Del.icio.us can bring lots of visitors in a hurry.

It is important to understand that sites like Digg and YouTube are not necessarily shock sites. Although there is some publicity to be gained from the shock value of an article or video, one must not resort to tasteless and offensive materials to gain attention. There is only so much value in the attention gotten by being the village idiot.

5. Buy text links on other sites

Although link buying is somewhat an unnatural way to build links, it may be the only way to increase your link popularity if your site is not unique or interesting enough to get people to link to you on their own. Most commercial sites fall into this category.

You should buy links in a way that simulates natural linking as much as possible. Buy text links from sites that are related to yours. Vary anchor texts and descriptions. Buy links from internal as well as home pages. Buy links from both high- and low-PR sites (which can be gotten at a bargain prices).

6. Participate in online forums

Sharing knowledge can be a very powerful way to establish your online presence and credibility. If you check your backlinks on search engines like Google and Yahoo!, you may notice that a number of them come from the signatures of forum posts, that is, if you post in forums. Most forums allow signature links. I don't participate in forums that don't as allowing them is the least the forums can do to compensate me for contributing to their contents.

7. Write testimonials and reviews.

Writing a glowing review about a product or service and submitting to your vendor or service provider can give you a very high quality link back to your site. But this strategy can prove time-consuming as many vendors publish only a handful of testimonials from their customers. Don't waste your time by sending a testimonial to a vendor who does not have a "Testimonials" page on their site. When submitting a review or testimonial, don't forget to mention to your vendor that they should be feel free to publish your comments on their site (along with a link to your site).

8. Ask vendors and clients to link to your site.

I once bought a $350 script package and asked my vendor if they could feature my site as site made with their script. They obliged and gave me a PR7 text link from their site. Since the link is worth at least $40 a month, my initial investement for the script has paid for itself many times over. Besides the SEO benefits, it is responsible for thousands of visitors to my site a month through direct clicks. The moral of the story: don't be afraid to ask. The worse that could happen is that they say "no".

9. Blogging

Setting up a blog is a no-brainer. Even if you've no web designing experience whatsoever, you have a blog up and running in no time. Blogs allows for a more informal setting to get your words across. So, it's much easier to write a blog entry than an article to submit to article directories. Use your blog to share knowlege, voice opinions, connect with others with similar interests, and of course, to link to your other sites.

Avoid spamming blog networks like Blogger and MySpace. These spam blogs ("splogs") are a waste of time as they will not get much attention from people and will yield little, if any, SEO benefits. Write about something you know and have a genuine interest in. Focus on quality rather than quantity.

10. Content is king.

Yes, content is still king. In fact, content is by far the most important of the ten strategies I've mentioned. Having fresh, unique, engaging content is an excellent way to attract natural linking from other sites. This is the type of links that search engines like.

You may have heard of the buzz phrase, link-baiting, that is being tossed around in the SEO community nowadays. The idea is to get others to link to you voluntarily, perhaps by causing some type of sensation or controversy on YouTube, Digg, the message boards, or whatever. Link-baiting, in my opinion, is no more than a new play on the old "content is king" mantra.