have you looked at elance and odesk? there are many pro's there for building prototypes and they don't bother usually stealing ideas. you can even make them sign an NDA first if you want to.
Stuff that I want to have well made and on time, I try to do myself or in house.
Plus I wanna understand this thing from the ground up. This is a biz I see myself running for the rest of my life once it was going.