This is just my opinion, but asking people for help building something is a bad idea. People with big egos will probably go on about how they're good builders, and know exactly what to do. I don't build well with other people because I'm the one with the big ego in that case. I always want to build what I think of, and get angry when they start doing something different.
First of all, how exactly do you "need help"? Is it really big, and you need someone to help build something repetitive, like large walls or something? Or do you not have any ideas, and want people to add their ideas to your build?
Either way, I just don't think you can trust someone to be able to help you. Too many chances that they'll get bored, or start trying to take over. I'd just build it on my own, if I were you.