Estimating local or long tail keywords

[BrandonWentland]

Google data show little or no traffic for some local and long tail keywords.  Do they just have a cut off that anything say under 50 keywords does not show up?  Is this data 100% accurate?  Are there other methods or tools for measuring this better?

Thanks much!

[EGOL]

Is this data 100% accurate?

One person could be responsible for all of the search for some long-tail keywords.

SEOs are known to be compulsive ranking checkers and can enormously inflate search counts.

Are there other methods or tools for measuring this better?

I would not believe any low-volume data.

I run adwords and bid enough to make the first page when I want quick volume data from a reasonably known source.