Freelance Illustration?

[strawhouse]

Hi All,
Does anyone here have any experience freelancing as an illustrator?
I think I would like to try this, I'm looking for some tips and tricks from people.
I've heard of a few websites that offer freelance work you can bid on (elance and ifreelance) not sure if these are worth it or not?
Not sure how else to get into this?
I've got a website for my fine art / commissions, I need to figure out how to market that as well. ( www.daynabarleycohrs.com ) The site is still a bit of a work in progress...
I'm working on throwing together a few illustration examples for a portfolio.... maybe targeting children's books?
Anyone know how you can illustrate for magazines?
Thanks for your help!!