I'm running my first tourney on Friday (small stakes, $10-20 buy-in), and I'm wondering if they are right when they say 50xBB is sufficient.

If you follow their advice, you start with 1000 and the blinds are 10/20. If you and an opponent get good starting cards, you can easily lose half your stack, even at 10/20. E.g., you raise 3xBB to 60. You get a call and the blinds fold. The pot is 150. If you bet the pot on the flop, and get a call you have a T450 pot. You've already put 210 in the pot and a pot sized bet on the turn and river will put you all in.

So I was thinking of using that blind structure, but starting with 1500. Good idea?

Also, because there will be some beginners, I was thinking of making it a rebuy tourney, so my guests won't be out in one hour and having nothing to do. I would assume that, for a rebuy tourney (rebuys only allowed in the first hour), T1000 starting stacks are sufficient because if people are eliminated, they can re-buy. Thoughts?