I use Overture to check how many people search for a particular keyphrase but I know it only reports on about 30% of actual searching. This is partly because it doesn't report on searches performed on Google. Does anyone know of a site where I can see how many people search Google for a particular keyphrase?
www.google.com/trends There really are no exact numbers published, everything is just an estimate. I suggest you find a keyword you know well/rank well in, and compare it to other keywords in Google Trends.
Google doesn't give out that info really but you can get the Adwords searches. I have a paid tool that does this. PM me for more info. Here is a list of seo tools. Some are keyword research tools. In there is also a MSN tool which I find very good. Overture is aweful and does not show 30% of the searches. Probably 80% of those reported are automated queries or webmasters checking their rankings. Here is the list of tools: http://www.1stsearchenginerankings.com/2007/01/14/list-of-useful-seo-tools/ I would just link you to the MSN tool but I think I deserve some credit for finding it EDIT: I should probably explain why I sent you to the MSN tool. I think the MSN tool is the most accurate and so you can gather your info there and make a guess at Googles traffic for that term. Some phrases in google get 10 times or more traffic than MSN does for the same phrase. So use it as a approximate guess at the traffic. Or you can get a tool that tells you the Google traffic.