Here is a list of some of the free advertising forums that I post in. If there is not an advertising section on the site, they allow signatures. Make sure that you read the rules and post in the correct forum or you might get banned from the board. Once you register in all of them, go through the list and post a message or two. Doing so will create thousands of backlinks to your website increasing your visibility in the search engines as well as all over the web.
With 2 links in your signature, you can have hundreds of links to your website in an hour or 2 per day using this list. Do it every day for 1 month and see what happens.