Bloggers who are starting off and think they are going to make milllions by placing Google Adsense on their blogs are extremly wrong, to a certain extent. Unless you have a few hundred thousand viewing your blog on a daily basis, google adsense will not bring you in enough revenue to earn you a living.
On another note, if you are just starting out blogging to make money I personally think you are in it for the wrong reason. The reason I personally blog is because I like it. Not for the money, because to be honest there is not much money in blogging (when starting off). Don't get me wrong, plenty people make a living off of google adsense but if you are starting blogging all I am saying is do not expect much.
But what I can say is, if you find a blog you like and they have adsense. Click on an add here or there.When I come across a blog that I like after reading I click on an advert just before clicking onto google to find more stuff. It costs me nothing and the person who owns the blog gets entisted to blog more. Also if you are starting off blogging, use twitter. Twitter is the best tool a blogger can use, along with email of course. Get in contact with other bloggers through twitter and email build up a bit of a friendship, add them to your blogroll and they will do the same. This brings readers to your blog along with some of your readers heading over to their blog. Comment on a few of their posts (most comment systems as for a url, so include that and thats advertising for you!).
Moral of the story, be friendly and people will be friendly back.