Here it is: Buy links from high pr sites. Yup, thats it. Out of all the link building I've done this one has got me the most results in the fastest amount of time. Yes, you could get free links by doing your own seo but that takes time and time is money. Plus most of the time, the links are very good priced compared to the results you will get from it. Also if you have a high pr site, make sure to sell links to get some extra cash.