"Well, first off, if there were large quantities of Atlas at Indy, would somebody please provide me with some e-mail addresses and phone numbers."
Bill Davis was the dealer with many tables full (at least at the beginning of the show) of brand new boxed 2-rail Atlas O and Intermountain cars for $25 each. Some guys were buying them a dozen at a time. You can contact Bill via his American Scale Models website and see what he might have left.
A different dealer at the O-Scale Convention in Enfield, CT this June also had huge numbers of new Atlas cars for $30 each or 4 for $100. I did buy a dozen from him.
In all fairness, the massive amounts of Atlas O Bill had at Indy appeared to be part of an estate sale.
And most appeared to be steam or transition era cars.