ST. LOUIS  – The St. Louis Public Library auditorium was filled with a cross-section of city residents: college students, small-business owners, church volunteers, working parents, the unemployed, retirees and more. 

What brought them together was a chance to learn more about a linchpin of the federal Affordable Care Act Ñ the online health insurance marketplaces that will give the uninsured a chance to purchase coverage in the months leading up to 2014, when those without insurance under President Barack Obama’s new health care plan face financial penalties.

 At the library, the policy expert from the Missouri Foundation for Health explained the labyrinthine federal program, outlining the four broad coverage plans (platinum, gold, silver and bronze) and eligibility standards. What she couldn’t yet provide Ñ three weeks before enrollment opens on Oct. 1 Ñ were the most important details on premium costs and coverage levels.

“We’re waiting,” said Akeissa Coleman, a health policy associate for the nonprofit group. “We don’t know.” 

In Nebraska, a 50-year-old single mother of three living in the city of Hastings can expect to pay about $1,000 annually for a silver plan covering 70 percent of health costs through Blue Cross Blue Shield. 

In Los Angeles, a 30-year-old single man opting for platinum coverage through Blue Cross would pay $332 each month for a plan with no deductible, $20 copayments for primary care office visits and a $4,000 annual cap on out-of-pocket costs. 

No such details are available in Missouri, where the insurance exchange will be operated by the federal government. State lawmakers and then voters rejected a state-run system. Missouri is one of 26 states ceding control of the insurance program to Washington, which is also teaming up with seven other states to run joint programs. Seventeen states and the District of Columbia are directly handling the programs. 

Federal officials said that despite the information void as enrollment approaches, consumers will have plenty of time to shop around once rates are known Ñ which they concede will likely not occur until the end of September, if not on Oct. 1. The enrollment period extends through March 31, 2014, with coverage starting as soon as Jan. 1 provided registration takes place by mid-December. 

Adele Sink, a spokeswoman for the federal Department of Health and Human Services’ regional office in Kansas City, acknowledged “a lot of anxiousness” about the absence of details in Missouri. She also encouraged prospective shoppers who don’t currently qualify for coverage from their employers to remain patient. 

“For the first time out of the barrel, we’re giving people lots of time,” she said. “There is a learning curve.” 

Small business owner Jim Price came to the St. Louis information session hoping to find out how much it will cost him to offer employer-backed coverage to his four employees and see if he can get a better deal on the private coverage he relies on for his family. He left the session without the particulars but confident he’ll benefit from the president’s signature plan. 

“It looks like I’ll be able to find a better rate,” said Price, who now pays nearly $11,000 annually for private insurance. 

Retired public school counselor Sonja Little, 62, doesn’t expect to partake in the exchange but wants to help members of her church navigate the system. She called the lack of information on program costs “a big glitch” that further hinders the ability to explain the complex effort to average folks. 

“There may not be enough time for people to understand,” she said. “A lot of people are frightened (by the new requirements). I’m thankful they had this forum, but we need some more help.” 

The law calls for trained “navigators” who will help guide consumers through the array of choices, along with “certified application counselors” from social service agencies, community health clinics and other groups who will assist with the actual enrollment process. But as with the details on rates that remain elusive in most states, the mad dash to get those people trained and certified persists.