Could you list the cons of using free hosted blogs in order to make incomes from programs such as adsense, yahoo publishet or msn??? Thanks
Two cons are that you don't own your site and that some people look down on sites without their own domain.
If you do go the free route, use a free blog host which does not put nay kind of ads on your blog, such as http://www.blogger.com and also http://www.blogurple.com (if you happen to prefer wordpress)
Just do a search on "blog deleted" in the forums and you will find some very good cons. Here is one threat for you to read: http://forums.digitalpoint.com/showthread.php?t=111156&highlight=blog+deleted
It depends on how serious you are and what your budget is. If your just starting out and only want to spend the bare minimum then buy yourself a domain and use free hosting. That way if you choose to buy hosting in the future you just have to move your files to the new host and you retain all your SEO goodness at all times because you own the domain.