Put two teaspoons of salt and half a teaspoon of celery seed into a marble mortar. Grind until the powder is uniform in color or you are bored out of your skull.
Because the oils are captured in the salt, this keeps fairly well.
Warning: Freshly-ground celery seed is much stronger in flavor than whole celery seed used in the same dish -- even if you soak the whole seed in vinegar for a week.
Quite a while ago I bought a packet of "product of Spain" "Paella seasoning with saffron". Inspection of the ingredient list showed that it was FD&C yellow #5 diluted with corn starch so you can measure it. Saffron was on the list -- dead last. I used one of the three packets in rice and forgot about it. A few weeks ago, I found the box, emptied one of the packets into a McCormick bottle, added about the same amount of seasoned salt, and began sprinkling a bit into my scrambled eggs.
Today I put a whole teaspoon of the mixture into the cup of rice I'm cooking for lunch (plus another meal or two cold or warmed over). That left about half a teaspoon, so I decided to open the last packet.
I added a teaspoon of turmeric to the bottle, then put a teaspoon of seasoned salt and a crank of "pepper supreme" into my marble mortar and ground the salt to a powder. Then I added a teaspoon of plain salt and ground some more. Into the bottle with the aid of a funnel, and the paellero direct from the foil-lined packet. I've yet to use any, but I expect the turmeric to dominate.
I ground half a teaspoon of freeze-dried garlic with two teaspoons of salt. If I'd been making it for just me, I'd have used equal parts.