• by Laurie Sullivan  @lauriesullivan, September 30, 2010

AdGooroo published a list of the fastest-growing verticals in paid search Thursday. The company estimates search spend for 246,214 advertisers across 3,515 verticals to analyze the increase, eliminating verticals with less than $50,000 monthly spend in either July or August.

Tracking top investments identifies an interesting trend in automotive-related sectors. GMC and Chevrolet dealers took the No. 1 spot for paid-search ads, spending $410,507 in July and $755,510 in August through AdGooroo. The auto repair maintenance and collision sector spent $196,876 in July and $592,849 in August. Auto accident attorneys spent $335,954 and $580,858, respectively.

Richard Stokes, AdGooroo founder and CEO, spent a good portion of his childhood hanging out with his father in an auto repair shop. He says the auto repair business typically slows during the hot weather and picks up in the cold as people get ready for the winter months. To answer my question on what can we attribute the uptick to, he calls dad -- who still runs his repair shop -- and learns that business remains "very, very strong this year due to the economy." People are not buying as many new cars. In fact, Stokes says some are digging out cars that have been parked for a year to get them running again.

Iceology Auto Analyst Chris Cedergren points to the need for automakers to increase sales after capitalizing on last year's Cash for Clunkers program. "Chevy was more in a defensive posture last year," he says. "They were in the midst of getting out of bankruptcy and now they need to rebuild the brand."

Cedergren also notes a decrease in ads for personal injury attorneys running on television, and wonders if budgets shifted from TV to the Web.

Timesheet software companies, sportswear and jerseys, and tradeshow display companies are among the big spenders, too.

In a research note published by Colin Sebastian, digital media and Internet analyst at Lazard Capital Markets, a check-in at ecommerce conference Shop.org reveals healthy growth in paid search, display advertising, and mobile devices going into September.

Keeping paid-search campaigns running well as the holidays approach will become important. Yield Software offers up to four search campaign tips in AdWords that marketers shouldn't forget.

1) Check the 'Let me choose' option to target only one network per campaign.

2) Create a separate campaign to target mobile devices.

3) Take advantage of AdWords extensions such as Sitelinks and Location.

4) Schedule ads by day of the week or hours of the day. You can increase bids for these time to make the most of campaigns.