Born/raised in the bay area, lots of small venues including 924 Gilman and Slims provided early exposure. Then there was "The List", I believe Steve Koepke started, which was a great way to track local shows.
I usually augment local with attending festivals in other cities (one such in Vancouver on and off for the last 15ish years), but as tastes change and more is available to us globally, true discovery is hard. There is a lot I find I like in passing, but bands I truly want to see live or hear more from, it's hard.
Youtube and, to an extent, the audio "platforms" I've you access, but there are no real good filters.
My best avenue, for now, is follow the musicians I know and follow up on who the like/are inspired by.