Is the back issues of Railmodel Journal still available,
I couldn't find the old website for the publisher; it was maybe a company circling the drain.
Your best bet is probably eBay. Between that source and swap meets (and with some patience), you could probably pick up any and every edition from 1989 to the end.
Good hunting!
EDIT Here's the publisher's street address:
RailModel Journal is long gone.The last issue was June 2008.Yes Ebay has them...but you will be paying alot for them, as there are many looking for the issues too