Spend 5 Bucks to get linked
Or you can spend $5.00 and get an account at roiclicks.com. Roiclicks is quickly climbing up the PR ranks and I think it's either a PR4-5 at the moment but it does get indexed frequently so might as well get your site there or even become an affiliate for free.
Other sites with free links:
And, don't forget to get listed on Biz.Url as well. You can even write your own articles along with your free listing. It's an excellent search engine boosting resource.