I used to make organizers out of foam and they worked out ok. Unfortunately I'm not a very skilled individual and came out all crooked XD
If you have the skill to measure and cut straight, which I don't, definitely consider buying foam sheets and wood glue on your local hardware shop. It's so cheap!
I believe I have. I made some stuff for Terraforming Mars, Castles of Burgundy, the Crew, Deep Sea Adventure and some universal resource trays. I think I only posted about the terraforming mars and universal trays in a single post