On-Line engine identification guide?

[GerFust]

I have a couple of engines from my childhood days that I would like to be able to identify. Those of us new to model railroading cannot simple look at an engine and know what it is. Is anyone aware of an on-line source to view different engines and identify them?

I am aware that Kalmback publishes the "Model Railroader Cyclopedia, Volume 2: Diesel Locomotives". $35.00 to answer a simple question is a bit steep. I'm looking for a cheaper, easier alternative.