I've been recording and playing with my voice since the age of 8. More recently, I've been doing an internet radio show, and doing character voices for an internet radio sit-com. I also make commercials and intros for other internet DJs.
I've recorded a couple "real" commercial voice-overs for a local cable company as well.
I am mostly self-taught. I listen to other voice actors and use their techniques to broaden my own voice work. It's amazing what you can learn by listening to the commentaries on Futurama and Simpsons DVDs!
I originally bought my home recording equipment to produce musical demos and songs, but found it equal to the task of doing voice-over and radio work. I can play guitar and bass, as well as sing, and I do all my own recording. I use Cubase for multi-track recording, and Adobe Audition for single-track recording/finishing.