You should contact paypal, but I would try and 
give the seller another week at least - paypal 
took a month to process my claim, but in the end 
did pay me back the full amount.  I had a seller 
on ebay that tried to screw me over- I had given 
the seller 2 months, he charged a very high 
amount for shipping, and could never provide 
proof that he had actually sent the item.  I 
think it helped that I had a perfect feedback 
rating on e-bay for paypal to verify that I was 
probably on the level.