Blogging is one of the fastest growing business trends on the web and it is an information based business. You don't need to invest any money to get started as there are free platforms you can utilize like Blogger, TypePad, Joomla and WordPress.
The information generally comes easy as most bloggers talk about something they know. If you have a particular subject that interests you and you are passionate about it, then its best to start a blog around a familiar topic to keep things fun and easy. Don't worry about not knowing enough about a subject, chances are you know more than most people in whatever it is that interests you,
You can also make money by inserting some ads from Google, Amazon, Clickbank, etc, to make some money. Or do a blog to help find a job, earn money from a business, find the chances your looking for by asking others for help and more.