If you are not building backlinks on a regular basis, you are missing out on the potential traffic that can come from higher rankings in the search engines. Free link exchange programs are good in that they allow you to have a source of other sites to exchange links with. However, they may not the best, as you cannot control the quality of where the links are coming from, since everyone can join.
Also, everything has to be done manually on both sides and can become time consuming to do on a regular basis. The best solution I’ve found is to participate in a fully automated link exchange system that manages the exchanges automatically where you won’t even have to manually add links on your site because everything is published dynamically via php from another server.
This is potentially the easiest way to build links I’ve ever seen! Check it out.