A couple of weeks ago, I started getting curious about what advertising categories are showing some vibrancy in local spot. Sure, the auto sector is a disaster, but I figured there must be some interesting signs of life out there in the universe. Seemed like a reasonable undertaking, given that I've written about the up-and-down vagaries of sectors in national spot for TVNewsCheck.

Then I ran into someone who put it to me straight: Don't try to draw broad conclusions with local spot. The relative strength of categories "varies so much market to market," said the source, who oversees ad sales at a large TV station group.

Greg Bilte, general sales manager at KTVU San Francisco, concurs: "It depends on the sales teams in individual markets and how aggressive they are."

My source explains that if one station gets traction with one type of business, it's not uncommon for other stations in the same market to follow suit. And there are so many potential businesses to target.

As Nexstar CEO Perry Sook told me, "Even in the smallest TV markets, there are 10,000 businesses registered with the chamber of commerce."

With so many bushes being beaten, it is hard to get a handle on what's working and what's not.

But I get the sense that legal, health care, home improvement, used cars, banks and furniture are all showing some buoyancy in certain markets. And, ironically, the growth is coming not despite the tough economy, but because of it.

It's easy to see that attorneys are seeking to capitalize on disputes arising from financial difficulties, but there's another huge reason why they're turning to TV in greater number: a general exodus from advertising in yellow pages.

That's according to Adam Armbruster, a partner in Eckstein, Summers, Armbruster, an advertising sales consultancy that works with TV stations across the country. The "mass migration" will take about four years, and we're about a year into it, he says.

Armbruster also reports that in some markets, new car sales are down, but used-car sales are solid. "While high-end furniture is down 20 to 30 percent, promotional and warehouse furniture stores are experiencing growth," he says. "And while home building is down dramatically, home remodeling is up."

He also notes that local banks and credit unions are increasing their TV exposure in some markets, at the same time national banks are reducing their presence.

Similar shifts can be seen in the health care category at WRDQ Orlando, Fla., according to its local sales manager, Charlie Sternberg. "We've always had hospitals with big branding campaigns," he says. But walk-in clinics "have really popped for us."

With unemployment hovering around 10 percent, Sternberg hypothesizes that the clinics are aiming at people who don't have insurance and need low-cost medical help.

Craig Smith, executive vice president of distribution and ad sales at the local online platform WorldNow, notes that one recent package of health care advertising garnered about $400,000 for a small-market station client, and another drew in some $1 million for a mid-size market station.

Unfortunately, sources tell me that in the process of luring advertisers that cater to penny-pinchers, some stations are lowering their own rates "dramatically."

But as Bilte and Armbruster point out, educating new customers about TV's great efficiencies is the best way to counteract that particular epidemic.

Spot Check is a bi-weekly column about TV station sales by Janet Stilson, a writer who specializes in the media business. If you have comments or ideas for future columns, contact her at 212-694-0126 or jstilson@nyc.rr.com.