Part-Time Opportunities for New Nurses?

Hi ~ I'm very seriously considering going into nursing. I currently run a home-based business and don't want to give that up, and I'm also planning on having kids soon, so a part-time nursing job would be perfect.

I'd have no problem working evenings or weekends, but want to aim for 20 hrs/wk instead of 40. Are part-time opportunities readily available for new graduates? Or do nurses normally have to work full-time in order to land that first job and then maybe cut back their hours after they've gained some initial work experience? Thanks!