While backlinks are very important, it is not all backlinks that carry weight. What I mean by this, is that not any backlink will increase your traffic. The important thing about backlinks are that they must be relevant links. Thh simply means that the sites that are linking to your site, must be about the same topics to let that backlink count.
Say for instance that you have a website about "SPORT", it will be of little use to you if a site about "FINANCE" links to your site. Sports and Finance are not related to each other. But if you have a website about sports and five other sites are about tennis, rugby, golf, cricket or boxing, it will be relevant links if they are all linking to you, but your site must at least cover all these different topics.
Please avoid link farms at all cost, cause these sites only spam the search engines and is of zero value to its visitors.
One of the things you can do if you want relevant backlinks to your site, is to search for websites in your niche and kindly ask the webmaster for a reciprocal link. Or if you want one--way backlinks, and your website is maybe about adsense, write a good quality article about adsense and put it on quality article directories with high pagerank. Such links are also relevant.
One other thing you should not overlook, is to pay great attention to your anchor text.. The achor text is that little yellow balloon which pops up when you hover your mouse cursor over a live link. If you place it in the URL of your backlink, it will look like this title='Adsense for BLA BLA BLA' or something similar. Experiment a little. Just remember that no method is the best method and something which might work for somebody else, does not neccesarily mean it will also work for you..
Just follow the basic rules of the search engines and in no time you will notice a fair amount of traffic coming your way.
One more thing. You are free to use this article on your website provided that it stays unaltered and the links in the resourcebox is live, search-engine friendly links.