My recent article 20 Must-Have SEM Tools listed 20 of the most popular time-saving tools you can use to help you with your search engine marketing efforts.

The article proved quite popular with both search engine marketers and webmasters, some of whom decided to send me their favorites that weren't included in the list. I also discovered a few more of my own since I wrote the original article, so I decided to add to the list by reviewing another 20 tools..