I recently discover this tool called keyword country where you can get the Keywords related to your query, Max CPC, Average CPC, No. of Sponsors, No. of clicks per month, No. of Searches, No. of Competing pages, R/S Ratio and much more. They will also tell you how to use those keywords and inject them in your webpages!
After viewing the video of how to use ( here ) I am pretty convinced about this product as it pretty much spells out the same thing I have done for my keyword research. One nice thing about this product is that it also gives you the comparison with Overture searches. Therefore making the analysis more generalize and trustworthy as relying solely on Google search results may not be convincing enough. You can take a look at the homepage ( here ).
Most importantly that I feel what more products are lacking is the trial tat keyword country is giving. You can take a look ( here ). Amazingly I convinced myself to buy a copy of this software and pretty much the result speaks for itself. I would recomend you to try and buy this software if you are seriously looking into how adsense can bring you sizable cheques.
Meanwhile learning everything from keyword country site and see for yourself if it is worth to take out your wallet!