There are two key trackers Overture and Wordtracker I do not know which one is the best though Overture is best in providing in regional wise data whereas it lacks in providing world wide data and whereas Wordtracker provides world wide data If i search for freewebspace both gives different results i do not know which one to take and also some one said about Google analytics please tell me how can I use it
None are really good in my opinion. Theres talk that wordtracker results are skewed (i dont know about this) and overture is never really accurate. until google allow access to their search database this is all we have to work with though.
in my experience, the results in Overture are pretty much useless. Word tracker is better but still way wide of the mark.