Seven Dwarfs: Fantasyland Great Wall, right next to Pinocchio Village Haus in Fantasyland
The Witch/Hag: Between the entrance to Enchanted Tales and the SDMT
Jack and Sally: Town Square Courtyard where Aurora meets during the day
Aladdin Characters: Adventureland just past the Aloha Isle. They are in a room inside, and a CM lets one party into the building at a time. You should see a line forming under a covered area immediately after passing Aloha Isle when walking into Adventureland.
Tarzan gang: Adventureland Verandah where Peter Pan usually meets during the day and where Ariel and Eric used to meet. Tarzan, Jane, and Terk meet here. You aren't guaranteed to meet all 3 of them, however
Jafar: Agrabah Bazaar where Aladdin and Jasmine meet during the day
Lotso and Buzz: They meet right next to each other where Buzz meets during the day in Tomorrowland next to CoP
Alice in Wonderland characters: In front of Mad Tea Party. You can find Mad Hatter, Alice, White Rabbit, and Queen of Hearts here, although they meet at different times throughout the evening
Captain Jack Sparrow: Adventureland stage across from PotC
Cruella de Vil, Dr. Facilier, Frollo, Tremaines, and sometimes Governor Ratcliffe: Club Villain, which takes place at the Diamond Horseshoe. They don't pose for many pictures and won't sign autographs.
You can also find characters like Tiana, Aurora, Snow White, Anna, Elsa, Ariel Cinderella, Rapunzel, Merida, Mickey, and the Pete's Silly Sideshow gang meeting where they meet during the day. Hope this helps!