Apologies for a very late entry into this discussion. Two thoughts immediately came to me:
1) What a brilliant article this would make, especially if converted into a guide to starting out in North American Modelling - something that new members could use to help avoiding buying the wrong things; and
2) Good OLD blue box Athearn - I think, Martyn, that the prices were in the £20-£30 range in 1994 because I started then and that is what I recall Victors charging and I think in those days the £ was not far off $2 so we got a good deal. But, there is nothing wrong in suggesting Athearn blue box locos today picked up secondhand - they can only fetch about £20 max. A visit to Brian Trains stand at any show will give a new starter heaps of ideas for stock at reasonable prices as they seem to have a huge quantity of USA stock just now.
If it doesn't fit above, try here!