The last time they played a few weeks ago, the Angels stole 4 bases in the 3 game series and that was with Dice-K and Byrd pitching 2 of the games. Keep them off the bases and they won't be able to steal, it's as simple as that. Now they will almost certainly steal more than 4 in the series, but i don't see it being some really high number.
Lester, Beckett, and even Buchholz have been good at keeping runners on all season, partly because they don't let many runners on, but also because they are good at holding the ball and throwing off the timing of the runners. The only time i can see the Angels really going crazy on the bases is when the bullpen is in, but i'm hoping we don't see much of the pen with Lester/Beckett/Buchholz going, and even if we do, as long as the bullpen does it's job then it shouldnt be a huge problem.