The novices might consider Google Keyword Tool to be the only available option. But the fact remains that it is only useful for the starters. The professionals can use more reliable keyword tools like SERPAnalytics. Though they are paid yet them come out as the clear winner coz of their features.
market samurai and google webmaster tools are the best ones to carry out keyword research (be it long tail or short tail or broad ones). There quite a few advanced tools too but then you need to be familiar with the basic tools.
I use Micro Niche Finder and Market Samurai to find long tail keyword, and I think that Market Samurai is better, but I think that in addition to using the tools, you have to rely on his own judgment .