I don't have one, but I would like one. But I still don't feel like I'm worth of a mentor. #impostersyndrome
I love helping people and I got a lot of my friends into programming and design and some of them now have careers because of my help.
Also, I give a lot of advices to people through internet. :)
When I decide to have a mentor I will approach some fellow developer who is my idol (superstar :D) over a Twitter or E-mail and just be honest with them.