L.G.
If you're talking about the newer ones, the people will eventually dry out if you just let them sit and air dry. I used to soak my daughter's in a bleach solution after they'd been in the bath a few times just to make sure they didn't mold.
Now for the bad news: if you're talking about the playsets like the bus or the firetruck or any of those... they will also eventually dry out on their own, but unfortunately if they used to light up or make noise they never will again.