For those of you new to the querying journey and wondering how you can even find agents to query, a very good place to start is https://querytracker.net/. There are over 1600 agents on there whom you can sort by genre.
A maybe slightly lesser known site is https://www.manuscriptwishlist.com/. This one you can also search by key word, so for instance if you want to narrow down to agents who specifically do "urban fantasy" you can look for that. There are often more specific details of what sort of stories they're looking for and what submission guidelines they're looking for as well. I've found most of my agents to query via Query Tracker, but I've started cross-referencing with MSW before submitting.
I also advise that once you find an agency's website, do a brief glance through of all the agents, even if these websites didn't list them as your genre. Sometimes people slip through the cracks, so you don't know what gems you might find.
If anyone else has resources to find agents, please feel free to share.
Happy querying.
This is a spectacular post! Great resources! I would also add Publisher's Marketplace as a great place to research potential agents and agencies.