File an Item not received at paypal they will handle the communication and also have a record of the communication. This will force the merchant to supply shipping and tracking information, which they should have already done. Shipping notifications are suppose to be automatic notifications to the buyer when the merchant uploads the tracking. Make sure you white list paypal emails and they are not in your spam folder, or maybe the merchant has not uploaded the information. An Inquiry or open case will get you started at paypal.

Depends on the seller's handling time. Since you bought through Paypal, you really don't have to worry. Contact the seller, and if you don't get a response, then contact Paypal. They will make sure you get your money back if the seller is MIA. But contact the seller first.

Did you tried to contact the seller via email? This is the first step