Superpages.com and eStara, a provider of call-tracking and conversion solutions, have signed on as sponsors of the Local Search Guide, the three-year-old online resource published by the Yellow Pages Association, reports MediaPost.

Local Search Guide tracks industry growth and offers an online directory of yellow pages providers, search engines and search tools. The guide also features an interactive homepage survey and a vertical directories category. ComScore, SEMPO and The Kelsey Group are Guide partners.

The new sponsors are a sign that online yellow pages are making a mark in the estimated $4 billion global interactive directory market - which consists of Internet Yellow Pages and local search.

The Kelsey Group forecasts the global interactive directory market to grow at a 22.3 percent compound annual growth rate, from $4.1 billion in 2006 to $11.1 billion in 2011.