There was an online index years ago, developed and run by an individual. When it became too much for him, it was bought by Kalmbach, publisher of Model Railroader and other print magazines.I see comments on blogs and forums that Kalmbach stopped updating the index, and then about last July they pulled the plug on it, citing security concerns, etc. I believe they said that it could not be fixed or updated because of the old language it was written in.
That put in motion a group that decided to start from scratch to build their own index, which was planned to be taken over the the NMRA. Apparently the NMRA is somewhat reluctant to take it on. Anyway, development of this "NMRA" index continues.
I thought that I would stop development on my own index, Rod Railroad Directory, which I have worked on by times for over 20 years. Then, late last year, the new NMRA index appeared. Hurray!
Backing up a bit here, I participated in a forum run by Model Railroad Hobbyist, the online magazine started in Jan 2009. I had some minor influence on its design, but they seem to have totally missed what I consider the very essence of a good index - flexibility.
I looked at the NMRA index and found that they had not been at all concerned about flexibility. Flexibility is being able to search for "boxcar", "boxcars", "box car", "box cars", "box-car" or "box-cars" and get the same results. This is not the case with the NMRA index. At this point I was really wondering if I wanted to be associated with this index.
The clincher for my decision came when I signed up to become an editor for the NMRA index. I entered one issue of Model Railroader to see what it was like. I found it a bit awkward, but that would probably get better as I became more familiar with their cryptic keywords. I submitted the items for this particular issue. The next day, I discovered I had made a keying error. Being a bit anal about such things, I pulled up the items (you get all the items for an issue), corrected my error and submitted. Imagine my surprise when the next thing I saw was that all the items had been added again - double entry. This sort of thing SHOULD NOT HAPPEN!!!. I have not signed in since.
So, work continues on an ever evolving Rods Railroad Directory.
In January the Kalmbach index, with a prettier face on it, returned. I hear complaints that it still has the same problems the original index had, and that a lot of things are missing. I can't say for sure. Only someone with an intimate knowledge of the magazine contents would know for sure.