In response to many people asking me about my photographs that I use for my paintings:
Find a box that fits the largest size photographs you have. Make divider tabs and organize your photos. Soon you'll find that you start taking photos of certain things like rocks, water, streams, trees, barns, mountains etc. so you can fill your box. Maybe you already have a bunch. I like having tangible photos rather than having them on a computer.
This box shown here had cookies in it I believe. I remember helping my Dad gather and organize these photos.
He used the large size recipe cards with tape at the top to make the divider tabs. These photos are from my grandmother and Dad. It's quite a collection. I had started making my own from a shoe box, but after my father passed away, I inherited his. I'm in the process of combining them.