All the electronics, etc. are gone because Sam stole them. Presumably to sell at a pawn shop for some quick cash (seeing as her and Lonnie are basically kids they don't have a lot of money to fund their escape).

FUCKING DOH!!! Of course! She even said "Please apologise to mum for the missing things" Man, haha, thanks Spider.

A letter and some bottles

1963

You can find the code in two places, written on a note under a secret door in Katie's "spare" room or by reading the notes in the father's study near his typewriter, though that requires more lateral thinking.

Inside is a letter from Oscar's sister, as well as a bunch of morphine syrettes and pills since he became an addict after molesting his nephew

I was prepared for the worst case scenario, but..well

girly coming-of-age feminist lesbian teenage trouble run-away

You are Kaitlyn Greenbriar, an independent-minded 20 year old student who has just arrived home from a self-discovery trip through Europe. But where is everybody? Mom and Dad are gone, your younger sister Sam nowhere to be found and she left a note on the front door that gives the impression something worrisome has happened. A storm is raging outside, thunder rumbles, the lights are flickering...an eerie atmosphere is created that immediately draws you in. It is now your job to find out what happened and to reconstruct the lives of the Greenbriar family via means of exploration. Opening drawers, cabinets, going through personal belongings, reading letters, documents, viewing photos and listening to their music. Soon you realize that the picture which is slowly forming is utterly mundane and every sense of menace a red herring. You will read about Mom's upwards career in the forestry department and her failed advances towards "Ranger Rick", some kind of idealized male object of sexual desire. The story of the previous inhabitant: the paedophile, remorseful Uncle, who has passed away and bequeathed the mansion to Katie's father. The fluctuating career of Dad who is a drunkard-loser-failed-sci-fi writer. And of course the centerpiece story of Sam, a highly intelligent, creative and rebellious mind who is in a troubled friendship with another girl. Or is it more than just friendship?
Yet even though it becomes apparent relatively early what the story is all about, the game still managed to glue me to my seat until the very end. So captivating and effective are the voyeuristic means of telling this story through discovery, so compelling the atmosphere, so engaging the act of empathizing with the family members that it was impossible to stop playing.
Gone Home manages something no game has ever done before: To masterfully tell a story that is ultimately generic, contrived, cliché and anticlimactic.