Last year, local advertisers spent $420 million on search advertising and according to Borrel Associates that number is expected to rise to nearly $1 billion and nearly double again next year, reaching more than $4 billion by 2010. Evidence that local advertisers have "gone beyond experimenting" according to the executive report. Eighteen months ago, local advertisers occupied just 5.6 percent of sponsored links on the major search engines; today it's more than one-third.