Motherboards.org - The Elusive Zen of Motherboard Identification:
"It certainly may appear to the inexperienced that there is some 'black magic' involved in the art of motherboard identification but really it only involves patience, determination and a little common sense in most cases. There is no doubt that those of us that have some experience do have an advantage in the ability to recognise some common model numbers or bios strings and in knowing the location of certain resources but all this really does is make the search quicker.

80% of the requests for motherboard identification in this forum can be answered in a few seconds by doing a search using the information supplied by the poster and a good search engine such as www.google.com

This can be done by anyone, 'guru' or not."

http://www.motherboards.org/articlesd/how-to-guides/910_1.html