No, they’re not Hollywood A-listers like Oprah or Ashton Kutcher, who have collected more than a million fans on the micro-blogging service.

Rather, they’re three relative unknowns from Northern California who, through tireless hobnobbing, nonstop posting and, in one case, luck, have joined a rare club: Twitter’s citizen celebrities.

All three — a business coach, a cellist and an entrepreneur — have tens of thousands of people following their musings. Depending on the perspective, the sheer numbers are a testament to Twitter’s power to connect people or simply a pointless popularity contest.

The service’s simple allure is allowing users to post brief messages about everything from politics to the tuna sandwich they ate for lunch.

Followers are those who subscribe to, and automatically receive, another’s posts. Amassing a huge number of followers is a badge of honor for many.

Those who have gained a measure of fame say it’s a way to meet people and share ideas, although they confess that interacting with their audience can eat up hours a day.

Inspiration, gratitude and soulfulness emanate from Shannon Seek’s posts on Twitter. The business coach, professional organizer and owner of a conferencing business is a supernova of positive energy, all day, every day, in cheery messages in which she shares blessings, online hugs and cosmic harmony.

“Twitter is a place I go to raise my vibration,” said Seek, who lives in Marin, Calif., and has attracted more than 53,000 followers.

Seek’s journey into Twitter’s upper echelon started as an outlet while she recovered from breast cancer surgery last year. She started following others, and many would follow her in turn.

Like elsewhere, there is a big appetite on Twitter for emotional pick-me-ups. When not broadcasting optimism, Seek, 40, replies to others who send her their good karma.

“The beauty of rebirth from the phoenix inside,” Seek recently wrote in one of her occasional Twitter poems, which, like all posts on the service, is limited to 140 characters. “My faith washes over me like the tide.”

On average, Seek posts 70 times daily. Her record is about 185 times, or one every eight minutes.

If the number of followers on Twitter is any gauge, Zoe Keating is more famous than Paris Hilton, Newt Gingrich and Justin Timberlake.

The professional cellist, whose avant-garde music draws modest-size audiences, got a big break when Twitter’s staff placed her on a list of suggested people to follow. By being thrust into the spotlight, her following — numbering around 8,000 at the time — catapulted by around 5,000 daily, for more than four months, to more than 777,000.

“I wonder if it was all a grand social joke by the Twitter founders to create someone who is famous who really isn’t,” Keating said.

Although glad to have such a huge audience, she also downplayed its importance. Some new followers, she said, send ego-deflating messages asking, “Who the hell are you?”

Keating, 37, posts from a shack among the redwoods near Occidental, in Sonoma County, where she composes her music. When on the road, she tweets from the tour bus or from backstage.

Because of her following, Keating feels compelled to post more frequently on Twitter than she did before, usually about recording sessions and other music-related topics.

“It’s hard on a musician when half your audience isn’t allowed to attend your concert because they are under 21,” Keating recently wrote.

Having more than 85,000 people follow you on Twitter helps when your dog is sprayed by a skunk, as Dave Malby can attest. He tweeted about his smelly pet, and got nearly 20 suggestions for eliminating the stench.

Malby, an entrepreneur in the Sierra foothills east of Sacramento, is a Twitter fanatic who has drawn a huge following since signing up last year. It’s his social outlet, business-networking vehicle and personal escape (his wife suffers from Alzheimer’s).

“It can really consume you,” Malby said.

About Twitter

Number of users: 21 million

Average number of followers: 126

Sources: Twitter, Nielsen Online (June — Twitter.com only)