Whilst there are many SE0 tools out there, most Webmasters acknowledge that to get the really powerful tools you need you are going to have to pay for them. But which ones are best for your needs? This is the question that is answered in this blog post which recommends the five best advanced SEO tools that are worth the money. The tools recommended include rank tracking, competitor research, link management and link marketing, link analysis and keyword research and content authoring. There are details on how each of these tools works and tips on how to use them most effectively. Many of the comments which follow the post will also give you an insight what other users think.