A little advice on contest since I have been doing them for years, when you start to promo your contest, make up the rules first, if you have to so many contestants then you should state that in the rules. Also how your going to pay out, and that sort of thing, if you want an example you can go to
http://www.awvns.com/contest.html I know its a pain, but it has cost me in contests because of double winners, ties, and things like that. Contest seem so simple, hey I am just giving away free money, but you will have loosers of a contest and sometimes they think they should of won, so you have to spell it out, because if you don't there can be legal remifications, and also your reputation can be at stake..
Question contest are hard because you can just throw the question into google, and poof there is the answer, when I do those kind of contests I use sponsor stuff, it helps promo your sponsors but also you can ask like what color is the girls hair on page 3 of such and such sponsor, so they cant be searched for.. and they end up actually going to the sponsor.. makes it a win win for you and your sponsors.. if you need any help with running a contest hit me up..