From DNK Web Solutions:
DNK Google Search Clone is an application written in 100% managed C# code. The application look and feel is very similar to that of Google, but can be very easily customized to fit your needs.
Full source code included.
2 aspx pages which you can easily customize.
The Webservice key is stored in the web.config file for easy modification.
New search can be started from the results page.
Displays the top 10 results from Google. This can be easily expanded to any number of search results.
The total number of results, search time, and search keyword are displayed on the results page.