Flush draws vs. top pair. odds?

[HardCory]

I have been playing a lot of internet poker this summer and I am constantly faced with this current situation on the flop. My question is not what move to make rather the odds of the situation occuring.
Hypothetically: I raise preflop and get one caller. I hit my top pair and there is two of the same suit on the board. Ex 8s 2h 3s
My question is what are the odds of him holding two sutied cards to match the board for a flush draw (two spades) in a 6 handed game? a 10 handed game?
How about what are the odds of being dealt any two suited cards preflop? and what are the odds that two cards of the same suit will come on the flop? (flopping four to a flush)

-Cory