yes, nostr watch has a large list.  and soon we can use nip66 draft to start building a distributed database of the relays in notes so that clients wont need to call nostr watch apis. 

 Any idea why nip66 is not listed here?:
https://github.com/nostr-protocol/nips 

 its still in draft, but its the real deal.. you have to search for its PR.  (search nip66)