Newbies starting out with link building usually make a mistake of building too many low-quality links at once. Keep in mind that Google isn't stupid. 100 links from fresh blogs won't give you much of an advantage in rankings (and they may even hurt your site). You have to focus on quality, not quantity. One of the best ways to build links (although it isn't exactly white hat) is to buy expired domains with high PR, and create a new site solely to use it for backlinking purposes. If you want to keep it white hat, build links by guest posting. It takes some time and hard work to make this strategy work (you have to write a lot of great posts), but it works like a charm. What is your preferred link building technique?