Google's showing a max of 311 phrase match searches a month for a 3 word phrase (I get variations of this phrase), but I'm getting over 5K visitors a month purely from organic results consistently for the past 7-8 months. Sadly it's not a buying keyword and it's something I didn't even optimize for, but it got me wondering because I've checked the search phrases in SEObook and it says the search volume is too low! Yet I'm getting hit almost every second for these phrases. It makes me think of how many keywords I passed by just because it showed no local volume, and very low monthly search volume. Is there a way to get a better estimate of search traffic for keywords?
I think that this is what you are looking for - https://adwords.google.com/select/KeywordToolExternal . .