I'd call that an internet blind spot. I know I have encountered them a number of times in the past myself. If the information is out there (and you would think it is), the search engines aren't providing a good enough way of distinguishing between contexts and eliminating irrelevant ones (such as "history" vs. "directions").
For my own part, I spent the past 40 minutes trying to produce better results. I can't tell if my general ignorance of knitting was an asset or a hinderance, but this was the best I was able to come up with:
http://www.iriss.co.uk/British_Breeds_Guernsey_Yarn.htm
I humbly suggest that if you ever find a suitable answer, you put up a web page about it. :-)