Deaths are somewhere in the region of 10,000 right now is terrible. As for help , if you wait a few days there will be fundraisers , all you need to do is a small chip to make a difference . I'm pretty sure this is going to take a while to recover and that will be expensive , so every donation counts .
12,000 people at this time, with more than that number missing. The status of 100 giant pandas in the Wolong Nature Preserve is unknown.
Where you live determines what you can do for them. I would donate money to the International Red Cross. If you live in China, donate blood. Google Panda and maybe there is an organization that will be fund an investigation into the missing Pandas. Keep your eyes open for news that will tell you specific needs - blankets, water, food, etc and the sites where you can drop off those items.