I saw him once on the back street at the Studios where Millionaire used to be (and I think One Man's Dream still is). They used to have a lot of character greetings in that area, so I don't know if they've moved them now that Millionaire's gone and there's construction going on.
Also, if you ask a cast member and they're not too busy, there's a number they can call to find out where certain characters will be in the parks that day and when. Good luck!
We saw him at MK last week in the queue waiting for Pooh and Tigger at the new Pooh garden in fantasy land. He was taking pictures but wasn't signing autographs.
What is the Pooh garden?
It's a playground for kids (complete with slightly squiggy floor) thats Pooh themed and is opposite the Pooh ride where 20000 leagues under the sea used to be