It's very important to look closely and pay attention to details. For me, ants are always smaller than I expect. A few months ago I, too, thought my area barely had any ant species except for fire ants. But I was walking fast and not looking carefully enough. Try looking at every tree you come across, there might be Camponotus or Crematogaster. Pay attention to the soil, and you might find small species like Pheidole or Nylanderia. Walking to find dealates isn't always the best method to find queen ants, but you can try walking early morning and you might get different results. You can also try black lighting which I believe will give you better results than looking for queens by foot. I use a 15 watt black light I got from amazon with a cord extention and placed it under a white sheet to amplify the attaraction, I've caught most of my queens this way. Finding queen ants isn't as easy as looking up a video and going outside sometimes, obtaining desired queens can take time. Where and how queens can be found can take getting used to the area you live in and can be different for everyone.