QuinStreet, an Internet marketer that competes with Yahoo and Google , is the one beacon of hope in this week's crop of initial public offerings as the market contends with jitters spurred by concerns about the economy, and I.P.O.'s from companies with more than their fair share of debt, The Associated Press writes. QuinStreet, of Foster City, Calif, sells pay per click advertising for financial firms and for profit education companies Sales have more than doubled since 2005, and analysts predict revenue will continue to grow as technology allows for targeted advertising through digital television