Amazon Links to the Gear I Use

 
I am not a full home studio yet, but with this equipment, I am able to create very good sounding demos and auditions when called upon.
 
The Digidesign Mbox is a USB audio interface (now superseded by the Mbox2), and comes with ProTools|LE, one of the "industry standards" in the field of sound recording. This is an incredibly capable program, but could be considered overkill for just voicing. But it can be worth the learning curve. There are other options that work with both Mac and PC, like the Mackie Spike and the M-Audio Fast Track. With these products, you would use audio software like Sony's Sound Forge or Mackie's Traktion (which comes with the Spike).
 
Why do you need things like these, you may ask. It's because the little mic input on your PC or Mac just isn't good enough for professional level sound, and no pro level microphone can plug directly into your computer, as they all use XLR connections.
 
If you are really interested in the home studio option, IMMEDIATELY buy The Voice Actor's Guide to Home Recording by Jeffrey P. Fisher and Harlan Hogan. They lay it all out for you in the best and simplest terms, AND they answer email questions.
 
For a sample of what I did with my very simple setup, listen to this...