How to find great keywords?

[pibefision]

I would like to know how to find great keywords, thouse cheap and usefull.

For example, I'm using Google on Spain, and find that the word "restaurant" has no search ads, and Google has 9 millon pages with that word.

Is that a great keyword or not?

Thanks, just trying to learn.

 

[dastuff]

If it has no ads how would you make money for it?

You mean is it good to advertise?

It's bad for both WH and BH if there are no ads for your keyword.

 

[pibefision]

Yes, i mean that there are not ads on that keyword.
Why is bad?

 

[Jdog]

Good for advertising on that keyword, but bad to make a niche site because you wouldn't get any contextual ads on your site.