Link Building is an important part of any SEO strategy. One of the first steps is identifying who you want links from. This list is probably very similar to the list of sites you're linking to. Now ask yourself what you can offer these sites in exchange for linking to you. Is your content so valuable that the site will link to you just based on the quality of your content? Some people practice reciprocal-linking, or offering to link to them if they'll link to you. Whatever way you choose to go about getting links, the practice of Link Building should be an important part of your SEO campaign.