Most Internet Marketing Linking Campaigns include having other sites link to your site. Establishing links from other sites has two major benefits:

The obvious, but sometimes overlooked advantage is that the link itself may help direct focused traffic to the site.
In addition, the important search engines place importance on links. Links from well ranked sites are usually best. Be careful not to link to or from link farms or other sites which have dubious goals. Good outbound links can also help an Internet marketing campaign.

Some sites may grant a link to your site on the condition that you link back. There is nothing wrong with this,however, links of this type should not be the only kind of you have. Site linking is the most important Internet marketing tool for improving search engine positions and should be combined with on site optimization which was covered previously.

Here are a few linking ideas:

Create content that people will want to link to.
Write articles or white papers that other sites will post with a link to your site
Distribute Press Releases with links to your site
Add your site to Web 2.0 social sites such as Del.icio.us, YouTube, etc
List your site on relevant professional sites
Submit your site to relevant government resources
Ask your partners and distributors to link to your website

A good way to pick up more ideas is to watch what others are doing. One way to get this information is to use the Yahoo link tool to see who is linking to a particular site. Analyze the results and you may find some good insights