No hard data for you but the last time I saw some of their car kits was at Des Plaines (IL) Hobbies about a year ago. I don't think they had the complete line by any means but they had more than a few. I suspect the kits did not sell all that well and that the bigger shops might have some unsold inventory -- and nobody to return it to. Des Plaines and Caboose Hobbies come to mind as the sorts of places that might well still have the kits on the shelves (or on the racks rather given the plastic bag packaging they used).
Ted Schnepf also tends to keep older items in inventory until they sell. He is a fixture at midwestern train shows. But I cannot say that I recall seeing those kits among the mountains of stuff that Ted sells.
Dave Nelson
All, I am looking for any information leading to the person/company that produced those HO passenger car laser cut kits from American Heritage Car Company or Northstar Railroad Models. I managed to find references to these kits from a walthers flyer http://www.walthers.com/page/wkw_upd12_na.pdf but walthers no longer carries them. I believe they were listed in the walthers catalog between 2003-2006 and in a MR magazine sometime in 2003. If any one has any information it would be greatly appreciated