So Im selling a couple of hundred dollar products on ebay and its going good. There was an order placed today by someone who has just made a brand new ebay account, literally hours old and he purchased my item. I am hesitant to ship it out. If I have tracking on the item, then have I done everything I need to do to be protected by ebay?
Yes, as long as you ship to the verified Paypal address.
what happens if buyer claims he got the wrong item and sends nothing back?
Then you risk losing the case, but that’s true of every transaction with every ebayer regardless of situation or rating.
I had this happen a few weeks ago. Buyer insta paid so I obviously had to ship out. It made me slightly paranoid, but I haven’t received any problems with this transaction. 
I know certain people here say it doesn’t make a difference if you do it, but I actually took a few pictures of the card and packaging that clearly showed the correct item(graded card) and the adress/tracking number. Some go as far videotaping the whole thing.
It never hurts to get extra documentation of the transaction in case something goes wrong. Tracking or registered mail are the best protection. Pictures and video are probably the next best thing.
Remember that new eBayers are often just that. They’re just new. Most of the time there is nothing malicious going on. I’ve had more trouble with experienced eBayers making strange claims than new ones honestly. If you really feel bad about the transaction just cancel it but know that doing that is not good for your reputation as a seller.