My site is 6 months old and it has 20 pages. The domain is exact match with my main keyword and it was ranked 13 for the medium competitive keyword without having backlinks.I have started link building last month. It was in top 6 for a while then gone. Now it is in 16th position. I build most links by social bookmarking, blog commenting, web2.0s and yahoo answers. I targeted for top 5 but its not coming. Now what more I need to do to get this site in top 5.