I would highly recommend doing a test campaign first with google adwords. Once you have a successful test campaign then turn that into a full-fledged campaign. After monitoring that for a couple weeks and if it still has strong profits then and only then expand to other search engines such as Yahoo, LookSmart, Kanoodle, etc. Remember you can lose a lot of money as well as make it so always test, test,and test before using up that budget and investment.
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