To be truthful, I should say everywhere.
Come to think about it, I like to watch people, and I like YouTube "talk" videos, those even in foreign languages. I can see a lot of gestures and stances in them. I am not sure I used any of those in a story, unless I did it subconsciously.
Then, once in a blue moon, a phrase or a line from a poem inspires me.
Most recently, I have been reading a lot of Dickens, and his storytelling skills have inspired me greatly.
In the story with Prep this year, for the main character, I am using two people I knew well and I added a bit to them. On the flip side, I knew one of them was wearing elevator shoes. So I Googled elevator shoes just to be exact, for when I write the story. Now, my inbox and any site or page I go to is full of ads for elevator shoes and insoles for men.