AA oop, i'm scared

[aggie]

Reraise more preflop. A read on the villian would certainly help postflop.

With no read, call and see what he does on the turn. If he pot commits you than you can probably give up your hand. A set is not that likely because he'd probably raise 99pf (so that leaves only 55)....If he checks behind on a blank value bet the river (provided it's a blank). If the turn is a spade you might want to seriously consider leading out and trying to take the pot away from a possible small flush.