The lid on my Lyman tumbler has a sifter built into it. It mostly sorta kinda works if you can keep a hold on everything. I take a plastic Wal-Mart sack, put it over the tumbler bowl and lid, then turn everything over and shake. That gets most of it. Then I pick the brass out by hand, making sure to turn it over and dump any media out of it before moving on.
If I have already deprimed the brass, I have to get media out of the flash-holes, too. The decapping pin from an old Lee Loader (the type where you use a hammer to do everything) works well for this.