It's the timeless question: how do you get other sites to link to you? The most commonly discussed ways are reciprocal linking (swapping links) and buying links. Yet there's another important tool for building links that should be a part of your toolbox: distributing content in exchange for one-way inbound links.
Comparison with Other Linking Methods
• Reciprocal Linking: The big advantage of content distribution over swapping links is that the links built are one-way, and therefore presumably more valuable. Of course, reciprocal links still have value, but relying primarily on them might hamper your SEO efforts.
• Indirect Reciprocal Links: I link my site A to your site, so you link your site to my site B. The problems are that this can be a lot of work, and also, Google can detect indirect links if you do it more than once with the same group of sites, which might make your linking arrangements look like a link farm.
• Paid Links: The problem with paid links is 1) the costs add up; 2) search engines are getting better and better at discounting paid links. According to Matt Cutts' blog, "I wouldn't be surprised if search engines begin to take stronger action against link buying in the near future...link-selling sites can lose their ability to give reputation (e.g. PageRank and anchortext)."
Kinds of Content to Distribute
• Articles. This is the essential kind of content distribution, to the point that many people consider content distribution simple as "article marketing." However, you're missing out on a few other sources of links if you only do articles.
• News blurbs. A lot of news-style sites will only reprint pieces of a couple of paragraphs. The good news is that often enough the whole point of these news blurbs is to include links to other sites, in a sort of "look what we've found" kind of way, a la Slashdot.org
• Press Releases. There are some sites that aggressively reprint press releases. A press release is like an article, only in a very specific press release format, and frankly that's not that enjoyable to read. I don't know why some sites are so head-over-heels over press releases, but, hey, that's their business. The good news is that even if you can't write and don't want to hire a writer, press releases (at least basic ones) are pretty easy to do.
• Tools, games and other webware. Sites with popular tools, software, Flash games and other webware often let other sites use it in exchange for a link. The big potential downside is technical support.
• Images. Images, especially charts and photographs, are important forms of content on the web. If you have great images on your site and people ask you to use them on their sites, require a backlink in exchange. The problem with images is that they are so easily stolen. Stolen words can be uncovered with a web search. You could try to watermark images with a copyright symbol, URL, and the link requirement. But in the process you'd make the image much less desirable.
• Web design templates. These have been freely distributed for a long time. Yet they are even more easily stolen than images. Also, if you embed a link in the footer of a web template, what you'll get back are sitewide links, which are often thought to be filtered out in search engines.
Maximizing Content Distribution Links' Effectiveness: Anchor Text
Anchor text. You need optimized anchor text to rank high for any competitive keyword. That means you need your target keyword in the anchor text, and very importantly, variants of the target keyword (too many links with the exact same anchor text may be filtered). The problem is that some sites by default don't let you choose the anchor text of the link to your site. So you need to: 1) look for sites that do reprint content with optimized anchor text; 2) specifically ask for your target anchor text to be used. Also, do keep in mind that a true natural linking structure will require you to have a number of links that are not anchor-text-optimized, typically with the URL as the anchor text.
How to Find Sites
Finding sites to submit content is the biggest challenge. You can start by asking around to any other webmasters you already have a relationship with. Next, web-search. The classic method is "submit article" + [keyword]. Most of the sites you find this way won't be good candidates, which is why this can be a bit labor-intensive. I use offshore labor for this step, as well as a program that will sort and store all the search results into a spreadsheet; otherwise it might not be worth it. Then again, the same would be true for finding reciprocal linking partners.
Ethical Issues & Best Practices
Golden rule: remember that there's a human being who has to approve your article for submission.
• Read and adhere to all submission guidelines.
• Avoid automation. There's almost always some detail of submission that requires a human eye: a multitude of html formatting requirements, changing site themes, etc.
• Don't submit by email unless specifically instructed. Using a contact form prevents possible sp@m accusations.
• Only approach websites that request content submissions.
• Don't misrepresent reprint content as original.
• Don't submit the same content too often. After about two hundred reprints, a lot of people will be seeing the same thing over and over again and possibly complaining.
In short, as SEO gets more competitive, having more and more linking methods at your disposal gets more and more important. Don't overlook this important tool.