I'm not sure if this is the best way, but what I did was :
- Asked my advisor for a list of what he believed to be the best programs in graphics
- Looked up websites of these schools and of the professors (many leave old pages, so it helps to verify if they are still at that school)
- Graphics is still quite broad, so I narrowed my list down to schools that had atleast a couple of ongoing projects in my research area (animation)
- Checked the last 5 years of Siggraph to see which school the authors were from
- Met a lot of interesting people at the last Siggraph, and got their thoughts on applying to their school etc.
Hope this helps.