Add Custom Search Engines to IE and Firefox

An advanced Google search technique can look within a single site, which is often a major help versus an internal search engine. (Recap: type your query, and then type "site:[domain]" such as "laptops site:pcworld.com" to look only at PC World.) But sometimes, I want the results from a site's own engine without having to click over to that site first. For example, a Wikipedia query that perfectly matches an entry will automatically load that page; Google won't. Here's how to customize the search bar in Firefox and Internet Explorer, adding direct searches on a range of sites. (link)