You may think that words like car, casino, and online gambling may be the most paid keywords on the internet, but that's not necessarily true.
Lets evaluate a common keyword. Poetry. Many people may want to publish poetry, so that's of some value to being of business use, but the vast majority of the ads that the keyword will be place in is personal teen poetry collections on the internet from teens using free sites that use google adsense automatically, like tripod.
It needs to more targetted or else you'll be getting 10 cents a click, while other keywords will give you $1 every click. It's simple math. Someone could be getting the same amount of clicks per day, but has different keywords or topics from their site. You get 100 clicks, they get a 100 clicks. You get 10 cents, they get a dollar per click. You get $10 they get 100$.
Actually the words that get the most money are kind of obscure, so that
Many high paying keywords are city targetted and deal with things that have an extremely high return of investment, like SEO, online universities, mortgage, automotive injuries, personal injuries, work injuries, anything mesothelioma(symtoms, specifics,etc), any drug lawsuite, law firms, etc.
Just think of some internet profitable service. Check what's new in your email spammers to see what they're spamming it's usually something high priced in CPC. There's no need to buy a list of keywords. Use the overture suggestion tool along with the google adwords keyword tool and see what are your possibilities for your site. It's a good way to make new topical content that your users will be interested in.