I doubt if there's any kind of "master list" for the internet, if that's what you're asking, but I can see on my server logs which search engines are used the most. I'm too lazy to go look up the exact numbers right now, but if I remember correctly, Google, Yahoo and MSN search engines comprise about 85% of the traffic to my site. I think the percentages would probably be close for most every website, too.
Hope this helps.