It is free for a weeks trial, then $149 for the full version. Or $97 if you purchase within the first week.
Have you tried Wordtracker yet? I found it to be more accurate. Have you done keyword research before? If not, let me know and I'll post more detailed instructions here!
I used Google Adwords tool , but now i am using the trial version of Market Samurai. I am loving the program and most probably i will buy it. So, i recommend you to use the trial version of Market Samurai at first and buy it if you like it.
I use the Google Keyword tool as well as it tells me what I want. I cant post the link on here but I also find Traffic Travis has served me well especially when looking at competing websites.
I started using this software by Brad Callen, great marketer and useful keyword tool. http://nichefinder.bradcallen (dot) (com).
Mostly I use Google Adword Key Tool and completely satisfied with this tool. Beside this some times I use keywordspy & rankpay. They are also good for keyword research.
I'll cast another vote for starting the initial keyword search with Google Keyword Tool, but to find the keywords that you can rank for, use Micro Niche Finder. I've used it for several years. A lot of marketers use Market Samurai.