There isn’t a Rancho Gordo store, per se, but the products are sold all over LA. The challenge is finding exactly what product you want.
For instance, I’ve seen the RG hominy at Farmshop and other places at times. Then, they won’t carry it at all for long stretches.
I do like their products and so do more of a bulk order a couple of times a year. More reliable than hoping my favorite products are in stock locally.