The searches, both in the McCleary area, cover so much ground that agents were brought in from the FBI, along with detectives in the Grays Harbor County Sheriff's Office and King County Sheriff's Office.
But an official said Friday that authorities have received "new, credible information" that there are locations in the McCleary area that may yield evidence to assist in the investigation.
Search warrants are being executed at those locations on Friday, and may continue throughout the weekend, said a spokesman for the Grays Harbor County Sheriff's Office.
Lindsey's mother, Melissa Baum, said she's cautiously hopeful about Friday's developments. "I'm trying not to get too excited, but this could be a break," she said.
At one site, FBI investigators in protective clothing were probing an area near an old, abandoned house and large shed about one mile southwest of McCleary.
At another location, about one-eighth mile away near the intersection of Old Sand Creek Road, North Sand Creek Road and Foreman Road, a mobile King County Sheriff's Office command post was set up at a residence surrounded by junk cars.
Officials said the people living in the house on the outskirts of town were asked to leave after receiving a search warrant.
Sgt. Steve Shumate of the Grays Harbor County Sheriff's Office said investigators spent hours Friday combing cars, gathering fibers, hairs, even the smallest clue that could tell them what happened to Lindsey.
"We know what she was last wearing," he said.
Lindsey's mother says everybody is considered a suspect. "Don't trust anyone anymore - it could be anybody," she said.
Lindsey's disappearance has baffled and alarmed residents of McCleary, a small town where everyone knows their neighbors.
Lindsey was last seen between 9 and 10 p.m. June 26 when she left her friend's home on Maple Street, where she had been visiting.
Lindsey was going to walk the four blocks to her home on Mommsen Road, which is roughly a 10-minute walk. But something happened in that short distance - Lindsey never arrived home.
On Saturday night, there will be an 8 p.m. candlelight vigil in McCleary to mark the three-month anniversary of the day Lindsey Baum vanished.
This is a developing news story. More information will be posted as soon as it becomes available.