I learn so much from my sisters. They'll hear a voice and say, "Where have we heard this before?" But they usually can call it before IMDB tells them. A common one is Sterling Holloway, best known for Winnie the Pooh. Here are some other voices he's done:
The Cheshire Cat from Alice in Wonderland
Kaa in the Jungle Book
Bridget was able to pinpoint that the mean flowers in Alice in wonderland
And Lucy knew that the White Rabbit from Alice in Wonderland...
...is Mr. Smee from Peter Pan. (Aka, Bill Thompson)