http://wordfast.fi/blog/?p=1030
Google's Custom Search Engine can be a convenient way to restrict searches to several specified domains, like the site:domain.com setting in Google's Advanced Search for a single site/domain.
Anyone can create any number of custom search engines for free, as long as they have a Google account. Each custom search engine can include any number of sites/domains.
This video shows how to create a custom search engine for Finnish newspapers that includes the websites of five newspapers, as well as another custom search engine for Wikipedia in three different languages.
Once a custom search engine has been created, it can be integrated into IntelliWebSearch (Windows-only). Please refer to the blog post mentioned at the beginning of this description for specific guidance.