You can see if your transaction is listed. If so, you can contact the seller under that tab on the right. That will send him an email through EBay so you have a record that you have tried to contact him. Could be that he does not have any other items for sale and is not checking. Maybe you can do an email check to see if you can find him through yahoo or sbcglobal, etc. Hope this helps. But at least, leave a paper trail by trying to contact him so when you file a non-received item complaint they will have the message with a time stamp.
Here's an idea...You used PayPal...go to your PP account and see the detail where they transfered the money (i.e. you are looking for an email address) Copy that address and send him an email using it. That will work for sure. Better do both if you think something is not quite right.