Seriously, everywhere. Look at your morning coffee, your egg mcmuffin, the trash on the ground, dirty dishes, your pen/pencil/brush, your hand, alarm clock, lamp,air conditioner, car/truck, train, train pass, dollar bill, debit card, credit card, the internet, the TV, cat, ferret, dog, a tree,a park, a movie, your family, homeless dude sitting next to you on the bus, the newspaper,a magazine, office, your job, your home, birth control or lack of it, your best friend, your most hated enemy, your ex, a funny website, youtube, your mom, air filters, dust, dust bunnies, a spider, a mouse, the vacuum an etc…
In short anything can inspire you to write/draw/paint in your art journal. Where do you let it take you? That's what matters.