We saw Mickey there around 1 PM. I know this because somehow our photos with him didn't get on our Photopass card and we had to search through the entire "Mickey gazebo" card to find out...LOL.
We saw Jessie in front of TSMM at many times during the day.
Pocahontas was behind BTMRR, kind of near where the water is, about 2 PM one day. Mulan and Mushu were over next to the Chinese restaurant in DCA at noon our last day there (saturday July 3).
You can almost always see Goofy and Pluto in Toontown hanging around.
Pretty much every day Cruella de Vil was in the Main street area--don't know what it's called, the front circle with the firehouse. Also the queen and Alice from Alice in Wonderland, Donald, Minnie, occasionally Mickey in the same place.
We went to the Disney Visa character meet and greet each day (this is the BEST deal--I think everyone should have a Disney Visa just for this perk!) and they rotate Pluto and Chip and Dale each half hour during the time they are open. It is amazing to me that they give you a voucher each day for a free photo--that's a $12 value!