I have had a sourdough starter for years and used it a lot. I love being able to bake without having to use any yeast at all. It is a much different taste than what commercial yeast has.
I keep my starter in the fridge. It remains dormant until I take it out and refeed it. But it takes a couple of days to fully rekindle the thing when I need it — using a custom-built proofing box to keep its temperature at a constant 85 degrees F.
If you elect to go this route, you can order starter cultures (dried) from Italy OR San Francisco from sources online. Make mine Italian — for a more refined taste. Just be prepared for VERY slow rise times. Takes me a day or more for each baking session, AFTER the culture has been restarted.