When did you buy?
I usually allow 20 days for delivery from North America and 30 days for delivery from Asia.
Did she provide a tracking number for your purchase?
If she did not, this is easy.
If the shipment is from Asia, after 30 days* from purchase, if the purchase has not arrived, go to the Resolution Centre at the bottom of this page and open an Item Not Received dispute.
If the seller cannot prove delivery (not shipping, delivery) you will be refunded.
If the item has arrived and has tracking, you will need to open an Item Not As Described dispute.
The seller will be told to send you a return shipping label. If she does not, you will be refunded without the return.
If she does send one, return the purchase and you will be refunded.
If you are too late for eBay Claims, go to Paypal.
Their Resolution Centre is at the top of your account page, hidden under Tools.
Follow the same steps.