For most websites, much of their traffic is driven by search engines. To see if your site is listed on popular search engines like Google, Live Search and Yahoo Search, type site: followed by (without space) your website domain URL. Ofcourse, this technique can also be useful to search within a specific domain.
All the above mentioned search engines provide tools for Webmasters to inform & manage the interaction:
On a personal note, about 71% of visitors to my blog come through search engines. In this year it has garnered a modest 16,000 hits with about 35% of the visitors from US.
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