Hooks, filters, API?

So you would search for location x, and instead of using the store locator db you would like to make it go through the custom fields from your custom post type? I assume the custom fields also contain the latlng values?

There’s currently no way to do that, but it does sound like a nice thing to add. I have to look into the best way to achieve that and make it not run the default store search query when an ajax request is made.