First, it’s probably within 3 feet of the place you thought it was and first looked. Maybe hiding against the black wall or something.
Second, you can look and look, and if you don’t find it, you won’t find it until you’re looking for something else and don’t need it anymore, so I try not to get uptight when I lose stuff. Although I just ordered an AirTag for my car key.

I started using a small flashlight. They always use one on detective shows, even in the daylight, they always find what they’re for.
Started as a joke but it seems to work.

My husband's copy of Shibumi & the hardware to a bed I'd like to set up again, are the two I'd like returned the most.

I know it has to be inadvertently tucked away in a box of papers or something--but I need a solid week of going though things throughout the house to have any chance of finding it. Yeah, I have some clutter, but I have gone through and reduced a lot of it--still coming up with no trace of the notebook. I have a goal to find it by New Year's because I have entries over a two-year period from about five years ago on the recipes I made and the daily lower carb/anti-inflammatory diet I followed that allowed me to lose and maintain weight loss pre-COVID. Without it, I am still making progress, but having that purple leather notebook would be so damned motivating!

Just buy another one. The lost item turns up within a day or two.

for cheaper items only!

Good one.

I'm not the only one with a list of hopefully temporarily lost items.