A "substantial reward" will be given to anyone who provides information that leads to Kelly Nolan's whereabouts, the mother of the missing Wisconsin college student said Tuesday.

"We know there is one more person out there that has the right tip," Mary Jane Nolan said during a press conference. "A sizeable amount for a reward has been determined and the doors are open."

Kelly Nolan's mother is convinced that her daughter is out there and that she will be found alive.

"I'm not crying today because I really have hope and if it takes money, we have it for anyone who has that last piece of the puzzle," she said.

Mary Jane Nolan also said police have spoken with all the individuals who were with Kelly throughout the night of June 22 when she went missing

"She has plans to be a journalist," Nolan said. "She would be out there finding your daughter someday and that was her dream."

Kelly's younger sister, April, said she couldn't imagine her life without her older sister.

"I don't want to be standing here crying because that's not what she would be doing," April said.

According to the family, Kelly had signed up for a journalism class the Monday before she disappeared.

A photo of Kelly Nolan's purse and the young woman's cell-phone records are among the leads police are pursuing in their search for the missing student, her family said earlier Tuesday.

Police have released a photo of a purse similar to the one Kelly was carrying on the night she disappeared in hopes that someone will recognize it. April, told FOX News on Tuesday that the 22-year-old's cell phone also does not appear to be working.

Police are still referring to Kelly's disappearance as a missing-persons case and are reviewing her cell phone records to see with whom, if anyone, she had contact in the early hours of June 23, when she disappeared.

Kelly vanished after she separated from three close friends in Madison. Her 20-year-old sister, April, talked on the phone with Kelly early that morning. That appears to have been the last time anyone heard from Kelly, who lives in downtown Madison.

A prayer service is set to take place tonight at 7 p.m. in Waunakee, Wis., Kelly's hometown, located about 15 minutes outside of Madison. Hundreds of friends and family are expected to gather to show support and give strength to the family, according to Megan Janeway, a friend of Kelly's who has been leading an effort to find her.

"It's really a chance for the family to take a break, sit back and realize how many people are out there trying to help," Janeway told FOXNews.com.

Her family continues to hold out hope that she will be found alive.

"She loved life. She had a lot of goals and plans and there was no reason to get away from the life she had and that's way I think she's coming back," April told FOX News Channel.

Mary Jane Nolan said the family will continue to pray for the safe return of their loved one.

"Police are working hard and tips are coming in. We've been displaying posters and looking and searching for her as well as having hope that Kelly is going to come back really soon," she told FOX News.

Police are also reviewing surveillance videotape from area bars and restaurants in Madison, where Kelly Nolan was reportedly spotted before she vanished.

"She's one of the strongest people I know," April told FOXNews.com on Monday. "She's the rock in the family and if she's put in a hard situation I know she is going to be tough."

April told FOXNews.com that she and Kelly spent all of Friday, June 22, together and split up around 5 p.m. in front of Kelly's apartment in the downtown area. Kelly then went out with three very good friends of the same age, she said.

Kelly separated from her friends at around 11:30 p.m., according to Joel DeSpain, a spokesman for the Madison Police Department, and she hasn't been seen since.

The police have located several people who were in the downtown area and had contact with Kelly the night she disappeared, according to a department press release. These people are providing detectives with new information, authorities said.

DeSpain said the missing student, who is 5-foot 6-inches, 125 pounds and has brown eyes and brown hair, was last seen wearing a green, sleeveless, scoop-neck shirt and blue jeans. She was wearing sandals with a heel and may have been carrying the unique handbag that was displayed in the photo that police released.

"We are getting lots of leads, but unfortunately none are panning out at this time," said DeSpain. "None of what people are telling us has led to Kelly."

April Nolan said she either saw or talked with her sister every day leading up to her disappearance.

"There is no explanation for what happened," she said. "I really have no idea what happened. It's not in Kelly's character to disappear."

Kelly Nolan was reportedly spotted at State Street Brats, a popular bar in the downtown area, hours before she vanished. But local police have said those reports are false and insisted that they were reviewing surveillance footage from many different local establishments.

But Tyler Kneubuehl, a manager at the restaurant, said police came to the establishment and told a manager that Kelly had been there the night she disappeared and they wanted the video footage from the security cameras from 11 p.m. to 1 a.m.

Matt Goetsch, general manager at State Street Brats, told FOXNews.com he had seen parts of the surveillance video and that "... Based on the parts I've reviewed, I certainly didn't see anything significant."

Goetsch said he did not see Nolan, although he acknowledged he did not view the entire video.

There are 30 surveillance cameras in the restaurant, according to Goetsch. But the cameras are geared toward tracking liquor and cash-handling behind the counter and do not place much emphasis on what happens in other parts of the restaurant.

Goetsch said there are a few cameras that concentrate on the crowd and that may have spotted Nolan, but none of what was taped that night can now be viewed. He said the cameras save the video for five days before the software overwrites it with new video. He said he did not know of any way that police could get the images from that night.

Nolan was fired from her job at the Orpheum, a bar and local theater, two days before her disappearance, according to local reports. Family members said she went to a job interview in Madison on the morning before she vanished.

The Nolan family has been meeting with police almost every day for briefings on the case. The family has also been handing out flyers in the Madison area.

"It's been consuming every hour of every day," April Nolan said, admitting that she really doesn't know what to think of her sister's disappearance.

Their mother has vowed not to give up searching for her daughter.

"We're going to find you, Kelly," Mary Jane Nolan told family and friends gathered for a candlelight vigil for Kelly last Thursday night. "We're going to be back the way we were before, as a family."

The Madison Police Department and the Wisconsin Clearing House for Missing & Exploited Children and Adults sent Kelly's photo and information to the National Center for Missing and Exploited Children Friday afternoon.

“The case is still being considered a missing person case as far as I know,” DeSpain said. "However, we haven’t ruled anything out. The evidence does not suggest that a crime has been committed.”

Madison Police said they were doing everything possible to gather leads in the case. Photos of Nolan were handed out around the community, which generated a lot of tips, police said.

“Patrols have been keeping an eye out and officers have walked the shores of Lake Mendota looking for any evidence,” DeSpain said.

The Dane County Dive Team has investigated area lakes, and so far nothing of significance has been found, DeSpain said.

154 adults have gone missing in Madison since 2001. 12 people have been reported missing this year, three of whom are still missing, including Kelly.

The Associated Press contributed to this story.