Paranormal investigators and video games

Third Grave Dead Ahead by Darynda Jones
Charley Davidson is back! And she's drinking copious amounts of caffeine to stay awake because every time she closes her eyes she sees him: Reyes Farrow, the part-human, part-supermodel son of Satan. Yes, she did imprison him for all eternity but come on. How is she supposed to solve a missing-persons case, deal with an ego-driven doctor, calm her curmudgeonly dad, and take on a motorcycle gang hell-bent on murder when the devil's son just won't give up on his plan of seduction...and revenge?

Reamde by Neal Stephenson
In 1972, Richard Forthrast, the black sheep of an Iowa farming clan, fled to the mountains of British Columbia to avoid the draft. A skilled hunting guide, he eventually amassed a fortune by smuggling marijuana across the border between Canada and Idaho. As the years passed, Richard went straight and returned to the States after the U.S. government granted amnesty to draft dodgers. He parlayed his wealth into an empire and developed a remote resort in which he lives. He also created T'Rain, a multibillion-dollar, massively multiplayer online role-playing game with millions of fans around the world. But T'Rain's success has also made a target. Hackers have struck gold by unleashing REAMDE, a virus that encrypts all of a player's electronic files and holds them for ransom. They have also unwittingly triggered a deadly war beyond the boundaries of the game's virtual universe--and Richard is at ground zero.