Kate is with Locke at the temple. Sawyer is either still at the barracks mourning the loss of Juliet or he's on his way to somewhere (maybe to the temple where he knows Kate came from, or back to the beach to look at his nudie mags before Ilana and company do some clean-up).
Well. The MiB did say that they were headed to the hydra station... So maybe Kate and Sawyer are there.