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Just because you've knocked off Google, Yahoo!, MSN, and dmoz doesn't mean you're done. Now it's time to locate specialty search engines and directories that your target audience uses. Take advantage of the search engine directories listed in Table 10-1 or simply search for directories and search engines by subject.
Use the Google Toolbar or Alexa.com to quickly assess the PageRank and traffic for these specialty search engines. Bother with only engines that appeal to your target audience and that seem to be maintained.