Cars niche? Real Estate? Vacations? Casinos? Snake oils like acai or medical stuff? I know sports and movies don't pay good.. only cents. So I avoid them. Same as "wordpress themes" or design stuff, by personal experience I can tell these one pay 0.01. .
ok.. but, is there any kid of relation between the sold spots of adwords and the price of the click? for example "Insurance": http://www.google.com/search?source...ie=UTF-8&rlz=1T4GGLL_enAR325AR325&q=Insurance does not have many ads sold on adwords while HOSTING: http://www.google.com/#hl=en&source...aqi=g10&aql=&oq=&gs_rfai=&fp=c88fe43dc3557e70 IS OVER-ULTRA-SOLD... incredible.. does "Hosting" pay good on adsense?? .
Legal and insurance related topics pay well. Think about how much things or services cost when you buy or use them. Most people pay a couple grand a year in insurance so big money to get business. Attorneys typically make many thousands on a case. Use the google keyword tool to get an idea. However, I have heard divide the amount listed by about 5 to get the amount you will actually get paid by adsense. However, this is not always true. I have a nutrition related site with url words that g keywords said was worth $.50 EPC. However, I average about $1 EPC for that site so pretty good.
I think if you use keyword spy you will be surprised at the volume of high paying keywords you can spy on.
Flights, Hotels, Student Loans... these all pay very well... if you get people to come to your site and click on your ads. The problem with some of these high paying adsense niches is that they are so saturated with competing sites. There must be millions of sites vying for the attention of visitors related to the most lucrative adsense themes. If you are new to the game you willl lucky to get any joy from focusing on these keywords. The best strategy would be to focus on real adsense niches that are only one to three keywords long, topics that are moderately popular but relatively unknown to other webmasters.
yes, you are right... here you get more high paying keywords..... http://ezinearticles.com/?99-High-Paying-Keywords:-The-Secret-Is-Out!&id=33537
I have a list of good ones you may like to use @ http://endlessscash.blogspot.com/2010/07/httpwww.html
Jobs is another good one, but if you're using an autoblogger make sure to set up a good filter because you'll pick up some things that can get you banned.
going for the highest paid keyword is a total waste of time. Your competitors will be too strong. I cannot stress to tell people this often because they just don't get it. Its like owning a hotdog stand and you want to compete against mcdonalds.