NASHVILLE, Tenn. — Americans spend billions of dollars online — a figure that grows by double digits every year. Now, several Nashville-area malls are playing catch-up in a bid to win more sales from shoppers comfortable with e-commerce.

Nearly 200 shopping centers nationwide have started letting consumers check online or via mobile devices to see whether a product is in stock at some of their stores.

They're going up against big-box retailers such as Best Buy and Circuit City that take orders for merchandise online and let consumers pick it up at local stores.

But the malls' service is not without problems: It's not available 24 hours a day, and not all stores at the malls participate.

"All of this is relatively new," said Sucharita Mulpuru, an analyst with Cambridge, Mass.-based technology research firm Forrester Research. Mulpuru said that store-inventory search engines had blossomed within the last five years. "There's a lot of interest in it and (retailers) are trying to figure out how to get there."

Los Altos, Calif.-based technology firm NearbyNow started offering its service exclusively to malls last year. Within the last two months, three Nashville malls signed up.

"The malls have lived in fear for the past few years that the Internet was going to put them out of business," said Dan Steinman, the California firm's vice president of customer relations. "The reality is, that's not true. The Internet could help us rather than hurt us."

NearbyNow attempts to overcome that with a decidedly low-tech solution.

Customers search for what they want online at a mall's Web site and get a list of stores and product photos. Then, consumers send an e-mail to NearbyNow to find out whether the product they want is available. Call-center employees make a phone call to the store to get the answer, and then send the shopper an e-mail response, usually within 10 minutes.

Shoppers also can send cell phone text messages to NearbyNow to get a list of stores currently offering sales. A recent text message using the word "shoes" for CoolSprings Galleria drew two responses: Lady Foot Locker and Buckle.

"This is done to help direct traffic in the mall rather than having to order it off the Web," said Hickory Hollow Mall's marketing director, Melissa Blackburn.

Die-hard mall denizen Stephanie Wild, 16, of Brentwood, said she would probably use the new online service. "I love shopping," Wild said. "I like coming to buy things instead of not buying anything."