1.Google Keyword Planner
2.Keyword reveler
3.Long Tail Pro

I think SEO Quake is a best tool for seo

I think SEO Quake is a best tool for seo

Wordtracker and Google keyword planner is best tool

I think Google keyword planner is the best keyword analysis tool.

Google Adwords Keyword planner is the good one and there are also many paid tools for keyword suggestions.

Google Adword planner is the best tool for the keyword research.