... and just to add my tuppence worth :
Think - IF YOU found out someone had been using YOUR credit card fraudulently and you found out who the eBay user was, would you send them an eMail like this - alerting them that you were onto them
.... and if you did would you go to the trouble of inserting a Button or Link to click on to help them out ?
I wouldn't - I'd make sure my Bank had cancelled the card to prevent any further fraud, and also pass all the info on to the authorites of law and order and let them make contact
The bottom line is - NEVER enter your user name and / or password for eBay, Paypal etc etc unless you are doing so on their secure website as indicated by the "s" after the "http" in the web page address : eg "https://signin.ebay.com........" or whatever.