I use Goodreads to track what I’ve read/listened to and my ratings, and then I dump it into LLM chat and ask for more recs. It’s not perfect but I get better recs than Goodreads itself.

I hear good things about https://joinfediverse.wiki/BookWyrm but I’m not sure it’s a drop in replacement for Goodreads.

Ask in the subreddit of the genre? Those are some of the more mature subs usually.