The Guangzhou International Toys & Gifts Centre should be what you are looking for. In fact, while close to Christmas, most of the light industry markets have gifts and decorations on sale.

There's a WanLing Plaza (a.k.a. Onelink Plaza) that sells alot of stuff you looking for. But i'm very sure, at this point of time, or even in june, you won't find Christmas stuff lying around. Walk to the street behind the Onelink plaza, and look around. You might find it.