Jen Diaz never parts with her two BlackBerrys, even when overseeing plumbing installation inside her half-painted store. Her scrapbooking and stationery boutique doesn't open for another two weeks, but she already has a substantial presence -- on Twitter.

She's closing in on 100 followers of her business account, people she hopes to turn into customers for her store, Oh Scrap!, after its grand opening.

"It is such free, great advertising," she said of the microblogging service. "People who don't use it are at a disadvantage, especially with the younger crowd."

The free service allows users to post short messages and distribute them to other users via computer or cell phone. Most people use them to communicate with their friends.

But businesses across the state -- ranging from Fortune 500 powerhouse Duke Energy to Raleigh's LoneRider Brewing Co. -- are joining the social networking site.

Small businesses are finding they can connect with a local audience and attract more customers through the Web version of word of mouth. Larger companies who might have dipped their toes in social media as they became popular say they're finding ways to turn the buzz into more sales and more effective customer service.

"There are more people understanding how to put real strategy behind it," said Jason Keath, a Charlotte-based social media consultant. Before, he said, they were interested more in quick-hit sensations, like creating a popular YouTube video.

The main goal of social media strategy is to encourage a two-way conversation between businesses and customers.

"Social media really brings home the relationship at the local level," said Wayne Sutton, a Raleigh-based consultant. "It brings folks in the doors."

It's a growing audience. Twitter's unique visitor count grew 1,382 percent between February 2008 and February 2009, according to Nielson Online. More than 12 million U.S. adults use Twitter, making up about 7 percent of Internet users.

Small businesses just starting out on Twitter usually begin using it in two ways: to update product information in real time and to get the company's name to the public.

Diaz will hold the grand opening for Oh Scrap! on June 13. She plans to send messages via Twitter describing new inventory, special events and promotions. She'll interact online with people around Charlotte to help build brand recognition.

Oh Scrap! also has an active Facebook account. Though that social media site has more users -- about 200 million -- businesses see Twitter as another arrow in their quiver.

Sumit Vohra, chief executive officer and "chief drinking officer" at LoneRider Brewing, uses Facebook and Twitter to advertise beer tastings and to check on customer responses to new varieties. "It spreads a lot faster on Twitter than other networks," Vohra said.

For larger businesses, Twitter strategy is focused more on adding a human element.

Raleigh-based Progress Energy uses it to get out news about power outages and to spread messages about new energy efficiency programs.

Duke Energy of Charlotte has about 600 followers on its feed. Michelle Pearson, Duke's new director, said the company also monitors what Twitter users are writing about the company. Pearson is helping develop a new strategy for Duke on Twitter, which will likely involve more direct engagement with customers, she said.