Well here in the east:
Harpers Ferry, WV
Point of Rocks, MD (inside a wye)
Havre de Grace, MD (station now gone)
Just to name a few within a few hours or so of me here in the Mid Atlantic.
Not all of these are still in use today.......
And many more may not have the actual sation located on curved track, but have curves so close that platforms extend onto a curve.
Depending on the era you want to model, the size of the town/city, and the region of the country, I suspect there are thousands of US examples.
Here in the Mid Atlantic, were the piedmont plateau actually meets the Chesapeake Bay, few railroad lines have long tangents, especially those lines running east-west.
When these rail lines were built, mountains, hills, rivers, existing towns, all required some rather "curvy" routes. As close as 10 miles from the tidal water of the Chesapeake Bay, the land is "hilly", requiring lots of cuts, fills, bridges and curves for railroad to built with exceptable grades.
Unlike the prairies out west, where it was easy to just "go striaght" on flat land.
I suspect a detailed search of the Mid Atlantic, New England, and even the upper Mid West would provide endless examples of stations on curves.
But again, region and era are likely everything to this question.
One more note - our model curves are sharp. I suspect that many real life stations on curves in the US are large enough radius as to be barely noticable standing at the station platform..........but many of the examples I gave are very obvious, by map or in person.