Google’s pay-per-click ad rates went up 14% in the second quarter of this year, when it accounted for 77% of search advertising spend, according to search marketing firm Efficient Frontier Inc. Google’s dominance of search ad spending exceeds its lead in search—Google accounted for just under 62% of searches by U.S. web users in July, according to web measurement firm comScore Inc.—indicating that many marketers believe they get better results from Google than from the major competing search engines of Yahoo Inc. and Microsoft Corp.

CPA2Biz.com, an online retailer of products and services for accountants, says it gets 15-20% of its traffic from Google natural and paid search, roughly 10 times the traffic it gets from either Yahoo or Microsoft’s Live Search.

“Nearly 10% of our overall online sales are driven from Google traffic,” says Melissa Rothchild, vice president of marketing services at CPA2Biz Inc. “We continue to find Google a very effective site traffic referral source.”

Google has always insisted its policies were aimed at delivering the best possible experience to end users, and those end users give Google high marks. The search leader scored 86 out of 100 in this year’s American Consumer Satisfaction Index, an annual survey by the University of Michigan’s Ross School of Business, up 10% from last year. Yahoo, Google’s closest competitor in search, slipped 3% in the survey to a score of 77 while Microsoft remained at 75.

Google’s growing popularity likely means still higher pay-per-click ad prices, experts say. “Google has been increasing prices for a long time, and there’s nothing to indicate that they will stop,” says Kevin Lee, executive chairman and founder of search engine marketing firm Didit. “But clearly they care about the user experience and reward the marketer when the user experience is better. That’s useful to the marketer depending on how savvy they are in search marketing.”

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