I think you can defiantly make 'good' money from a blog.
I have seen a few examples.  I guess they have been working on their sites for a while.  I don't think there would be a fast buck to be made. But, hey if you enjoy what your writing about and have the time, you can get there.

Here's an introduction to making money from your blog at Site Sketch 101.

Link to Article

It's possible, but it depends on a lot of factors and you need to be very passionate about what you do as well as patient and hard-working...

According to Gary Vaynerchuk and Crush-It, if you have enough passion for what you blog about and work crazy hard... It seems you can.

An ideal starting point would be: www.viperchill.com (Glen Alsopp) very insightful with great tips and structure.

Http://www.livingroom.org.au/blog/blog-earnings-October-2008.jpg

that could give you a good idea (2008 numbers).

Yes you can. But don't look on blogging as "get rich quickly" sheme.
Look at www.problogger.com for more infomations...

Thanks for the input, the graph up top made me a little nervous, but who knows who he polled, most might be people on his site who are just starting