Authorities are forensically investigating those computers and are also examining devices owned by Ryan Lanza, the gunman's older brother, to see if they can learn anything more about Adam and what caused him to snap.
The magnitude of Lanza's arsenal was confirmed today by Connecticut State Police, who said the 20-year-old had hundreds of rounds and used multiple high capacity magazines when he went on the rampage at the elementary school.
After shooting at victims in two classrooms and a hallway with a high-powered semi-automatic rifle, Lanza put a bullet into his own head with a handgun.
"The weapon that was utilized most of the time during this horrific crime was identified as a Bushmaster AR-15 assault weapon," Connecticut State Police Lt. Paul Vance said. "The trajectory of the shots and all of the ammunition used in the horrible crime will be examined."
Vance said three weapons were found at the scene, while a fourth, a shotgun, was recovered from Lanza's vehicle.
ABC News has learned that both the shooter and his mother spent time at an area gun range, however it was not yet known whether they had shot there.
At a news conference today, Vance warned of misinformation being spread on social media by people posing as law enforcement or the shooter.
"It is important to know, we have discussed with federal authorities these issues are crimes. They will be investigated. ... Prosecution will take place," Vance said at a press conference, adding that all information has been and will continue to come through him.
Post-mortem on Shooter, Mother Complete
The medical examiner's office completed the post mortem today on Lanza and his mother, Nancy, who was shot in the head several times before her son went on his killing spree, officials said.
Adam Lanza died of a single gunshot wound to the head, officials said.
This morning on "This Week," Connecticut Gov. Dan Malloy told George Stephanopoulos that Adam Lanza likely heard first responders and took his own life.
"We surmise that it was during the second classroom episode that he heard responders coming, and apparently at that, decided to take his own life," Malloy added.
As the community mourns and families bear the pain of planning 26 funerals before Christmas, school board members hope to get students back to a familiar routine.
"Well, all the mental health experts we've talked to ... tell us that the best thing we can do is to get back to normal operations as soon as possible," said Bill Hart, a member of the Newtown Board of Education.
"We know some teachers won't be prepared to come back," he said. "We are going to be prepared with substitutes. We've got counseling for all. We're prepared to do whatever we have to do to help all of our community."
The town of Monroe has offered to open Chalk Hill School, which is not currently being used, to Sandy Hill students and staff, the Newton Board of Education said in a statement.
The neighboring community's school is expected to be ready to accomocate students in the next few few days, however an exact schedule has not yet been published.
Hart said officials did not yet know what would become of the building that was turned into a slaughterhouse on Friday.
"I think trying to understand what we are going to do with that is a long process and we're not in any way prepared to make those decisions now," he said.