In May, we saw Chicken Little and Abbey Mallard by the Big Hat at MGM. They used to be in the Animation Building and maybe could be in there still sometimes, but it seems they are most often by the Big Hat. They both sign autographs. Clarice was meeting by the Big Hat in May and June, and I think she is still getting out. Clarabelle and Horace were spotted in ToonTown at Magic Kingdom, but only on a handful of days and it may have been a "test" thing, so I am not sure if they will come out anytime soon! The Cars characters are at MGM, driving around at certain times in the day. Brer Fox was out in May and June at the exit to Splash Mountain, but he's quite rare!
As for Narnia, last time I heard, the White Witch is not a meet-and-greet character. She usually does make an appearance in the Narnia Exhibit, but she is part of the "show" and does not meet people at all in there.
Other new characters include the four Little Einsteins, as they have been meeting on Mickey Ave at MGM. They seem to have become pretty regular, though I am not sure how often all four get out. And Kim Possible and Ron Stoppable are also meeting at MGM, either on Mickey Ave or the Avenue of the Americas near Lights Motors Action.
Hope you find your favorite characters!