I need to say you have a really nice voice, but PC microphone is surely not enough for good voice acting or voice-over records. I'm affraid it is gonna be hard as hell for you to get hired, unless you invest in some condenser microphone, which is an absolute minimum (as some sort of a studio would be recommended as well).
I wish you good luck, as I really like your voice.
PS: If you would like some tips/advice on hardware - hit me up. I am not a expert on it, but I know a little