Originally Posted by BradCallen
Utilize your offline friendships and professional relationships to find some link buddies! Also, learn what the absolute selling point is of your site or offline services. Too many people jump right in and start building links the easiest way they know how. Sometimes a little sweat and elbow grease will get you much further than building links on blog comments, article directories, or social bookmarks. Google undoubtedly understands and utilizes the difficulty aspect and anywhere you can easily build yourself a link isn't going to count as much as a legit business-related site with very few outbound links.
This is a really important tip. To expand on it further, like with any friendship it is a two-way street. You cannot expect to get a network of friends who will willingly promote your site/blog/forum/art-gallery/etc. unless you are also willing to spend time doing the same for them.
Too often link building is done in a lazy and haphazard way and it is why people continually complain that their efforts are going unnoticed. When you truly grasp each concept and give it the time and attention it deserves you will be rewarded with the corresponding results.
Building a network of friends isn't easy. You don't just add tens-of-thousands of random people to your twitter profile, then set your tweets to auto and promote the hell out of yourself and expect to get noticed. Someone with 100 followers who are genuinely following them because they are interested in what they have to say and who they are is going to be far more successful.
Take the time to talk to and get to know people in your social network who are related to your area of interest. You might even make some genuine lifelong friends (go on I dare you). Share ideas, help each other market, and create real business relationships that get you and your friends ahead.
You have to push each other to achieve. Adding a reciprocal link to each others sites is going to do nothing to promote your business. You need to actively promote each other, not just add passive links and hope that people click on them.
The reason why link building almost always fails, is because people just "build links". When you have a social network, you aren't just building links, you are promoting and sharing with friends, and getting information across to people that matter. Yes, you are linking to people, but you are doing it because you want to, not because it is work. That's the difference.
When you descend into that "dang I'm spending 2 hours today building another 10 links" mindset --- you've failed.