Oak trees host a lot of gall-forming wasps (tribe Cynipini), many of which are documented fairly well on iNat. But two of the big categories that are massively underrepresented are bud and flower galls. They’re much smaller, more ephemeral, and easier to miss, but I think often quite abundant when they occur, so if you go looking for them I think you’ll find a lot. Many if not most of these would be the coveted “first for iNat” species, and for many of them, color photos don’t even exist.
@jeffdc has already found a bunch in VA (eg this one on white oak) so there are probably a lot to be found in the southern half of the country. As spring hits your area, pay attention to your local oaks and see how many you can find!
@calconey wrote a good general note on where and how to look for galls which applies well here. For any gall observation, it’s important to also document the host plant in enough detail that its ID can be confirmed, if you’re not sure of it yourself. For spring oaks, get a picture of any old leaves from last year or spring leaves from this year if possible, of the buds themselves, the whole plant, and of the caps of acorns if present.
Spring galls are probably easier and faster to rear adults from than galls in other seasons, so if that’s something you’re interested in trying, this would be a good opportunity. Collect any galls you find and put them in a container (glass jar with peat/sand mix or just a fine mesh bag seem to be best). It would be great to have new, good pictures of these galls with IDs confirmed by adult anatomy.
Happy gall hunting!