The documents are part of the Peteypedia, the personal files of FBI agent Dale Petey (who will appear in the show and be played by Dustin Ingram). So far only four documents are available for viewing, which more probably coming as the season continues.
Summary of each is below and spoil aspects of the first episode, so please be aware if you have yet to see it.
THE SQUID -- Veidt's fake squid attack on NYC at the end of the comic is referred to by the FBI as a Dimensional Incursion Event. The squid itself is called an "EDEB" but there is no explanation for why it's called that. The squid dissolved into a watery substance before scientists could study it. Scientists have currently no explanation for the random squid showers like the one in the first episode.
LAURIE AND DAN -- Nite Owl and Silk Spectre continued costumed vigilantism after the event of the comic, with Laurie taking the name of The Comedienne. They were both arrested in 1995. Laurie is now an FBI agent and will appear on the show, being played by Jean Smart.
ADRIAN VEIDT -- Adrian helped elect Robert Redford as the new President and became the biggest contributor to that world's Democratic Party. Veidt tried to get the world to become a more tech-based society, but most tech was destroyed after the squid attack and has only just recently returned. He lost most of his fortune, left public life in 2007, was declared missing in 2012, and "presumed deceased" as the series begins. Petey disagrees with the declartion, stating it could rile up right-wing groups like The Seventh Kavalry.
RORSCHACH'S JOURNAL -- Rorschach's journal entries are published but the public brushes them off as conspiracy theories that cannot be proven, and thus have no lasting impact on the world.