Here are some free tools for finding the frequency of searches for your keyword phrases.
NicheBot Classic
NicheBot Classic used to be just NicheBot, until NicheBot v2 was released. It offers quite a lot for a free tool. I use NicheBot v2 quite a bit.
Wordtracker
Wordtracker’s free tool shows 100 variations on your keyword phrase.
Keyword Discovery
Keyword Discovery also shows 100 variations on your keyword phrase, and some sample stats from their paid service.
Google Adwords External Keyword Tool
Google’s tool gives useful suggestions, but some of the stats are shown as little tiny bar graph things, not real numbers.
SEOBook Keyword Tool
SEOBook’s tool estimates the monthly searches based on the Google, Yahoo Search Marketing (Overture) and MSN keyword tools. It provides links to the Keyword Discovery tool and the WordTracker tool. It also provides links to searches for your keyword phrase on news sites, blog directories, classified ads, EBay, Wikipedia and many more.

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I use these tools myself and they are great !
Researching the correct keyword to target is vital in any online businesses.
I pretty much use the Google and Keyword Discovery tools.
For your keyword research try using KeywordSpy – a keyword research technology that will help you know what keywords your competitors are using and how it generates money for them, you can use those keywords to drive traffic to your site and give your business the exposure it needs. It offers Free trials.
It goes with a ClickBank Affiliates Search Engine where you can see the actual market landscape at ClickBank.
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