I found some ad prices base some keywords (by some high pay keywords article or tool) is as high as above 50$ . So I create a site that contain the keywords and question: how to make sure the high paid ad is displayed on my site? and I just get one click one day. I will make 50$(or 20$) per day. so Does it work in real world?
Get an AdWords account and figure out what keywords are paying. Build a site around those keywords. If you can get traffic you will make the money. Ideally you stick to what you know but cater your site to the higher paying keywords in your area. Personally, I just mirrored 4+ million Wikipedia articles on my $7 a month GoDaddy account. So far I'm averaging about 20 cents per click and Google/Yahoo are having a field day indexing the site. It'll be interesting to see what happens in the coming months. My ringtones only site averages 30 cents a click or so. The focused site makes more but we'll see which one gets more traffic.
Ya but most of the expensive keywords have a super high competition.. If you build a site now.. you might not see revenue for 1 year..