You might try clicking on this link and entering in your tracking number. The China Post Offices web site can be found by clicking here. The problems I have encountered with most postal services is once the parcel leaves the country it can no longer be tracked. Other countries do not track packages that come from different countries. Do you know how the package is being sent?
If it is being sent air you should have it in less than a week. I know I ship packages all the time to China and they get there in a week unless the post office screws up and sends them surface. Then it can take 2 months or more and it has happened to me. Did the person sending you the package give you a web site to track the package on?
That does give you a lot of protection. You need to start a item not relieved process with PayPal. It does take awhile but they will refund your payment. Just make sure to follow with the information that PayPal ask for. As far as ebay helping I have found them to be useless.If I can help please let me know.