I got them at a local nursery!

But I was also told by a plant geek friend that folks grow them on the side of the road, and there are quite a few "semi-public" (true) bay laurel trees in most places in California if you know where to find them. They grow exceptionally well here since they are a Mediterranean plant. We also have a native California bay laurel variety that grows quite well in southern California without much care at all. They taste pretty similar and it's EXTREMELY easy to forage. https://www.foragesf.com/blog/2019/10/5/california-bay-dont-buy-bay-forage-it