Google has unveiled its Google Custom Search Business Edition service that allows small businesses to add search functionality to their websites. 

Small firms can sign up online for the hosted service, which allows visitors to search their site using Google technology.

"Millions of businesses have a web presence but offer no ability to search their site," said Dave Girouard, vice president and general manager at Google Enterprise.

"While many of these businesses invest in search advertising and search engine optimisation to help customers find their business, customers are left on their own to navigate content once they land on a site."

When the customer has identified the site to search, and chosen all or selected areas of content, they can add the search box and customise the appearance by adding logos and matching the site's look and feel.

They can then further customise search results with refinements that reflect site content, such as section groupings.

The Custom Search Business Edition builds on the Google Custom Search Engine, a hosted search programme introduced in October 2006.

This adds business integration features through an XML API, the option to turn off ads, a more customised look and feel, as well as email and phone support.

Google Custom Search Business Edition joins other offerings from Google Enterprise, including Google Search Appliance and Google Mini which offer additional control over crawl depth and timing, as well as secure access to internal documents.

Because the site search is hosted by Google, it eliminates the need for small businesses to install and maintain their own technology.

Google Custom Search Business Edition starts at $100 a year for searching up to 5,000 pages, and extends to $500 a year for up to 50,000 pages. Above these levels companies are referred to the Google Enterprise sales group.